**Rule**: Sentences with a reporting verb (like expect, believe) and a 'that'-clause can be made passive in two main ways: using an **'It...'** structure or by making the subject of the clause the new main subject.

- **Correct Answer (d)**: Both (b) and (c) are correct passive transformations.
- (c) **'It is expected that they will pass the exam'** uses the introductory 'It' followed by the passive verb and the original clause.
- (b) **'They are expected to pass the exam'** makes the subject of the 'that'-clause ('they') the new main subject, followed by the passive verb and a 'to'-infinitive.
- **Incorrect Answer (a)**: This version is unnecessarily clumsy by making the clause passive as well.
- **Incorrect Answer (b)**: This is correct, but (c) is also a valid and common transformation.
- **Incorrect Answer (c)**: This is correct, but (b) is also a valid transformation.

**Rule**: When the active sentence uses 'will have to', the passive form is **Object + will have to + be + V3**.

- **Correct Answer (c)**: The object 'its operations' becomes the subject. The structure 'will have to be expanded' is the correct passive form for the future necessity.
- **Incorrect Answer (a)**: This omits 'have to', changing the meaning.
- **Incorrect Answer (b)**: 'would' is an incorrect modal change.
- **Incorrect Answer (d)**: This is the passive of the Future Perfect Tense.

**Rule**: For a negative sentence in the Simple Past Tense, the passive voice structure is **Object + was/were + not + V3 + by + Subject**.

- **Correct Answer (b)**: The object 'his application' becomes the subject. The passive verb form 'was not accepted' correctly reflects the negative Simple Past tense.
- **Incorrect Answer (a)**: This incorrectly changes the tense to Past Continuous.
- **Incorrect Answer (c)**: This incorrectly changes the tense to Present Perfect.
- **Incorrect Answer (d)**: This incorrectly changes the tense to Simple Present.

**Rule**: When verbs of perception (like see, hear) are followed by a present participle (-ing form) in the active voice, the passive form retains the present participle. The structure is **Object + was/were + V3 + present participle**.

- **Correct Answer (b)**: The object 'him' becomes the subject 'He'. The verb 'was seen' is the correct passive form for the Simple Past. The present participle 'opening' remains unchanged.
- **Incorrect Answer (a)**: Using a 'to'-infinitive ('to open') would be correct if the active sentence used a bare infinitive ('saw him open').
- **Incorrect Answer (c)**: This makes 'The box' the subject and creates a more complex and less direct passive construction.
- **Incorrect Answer (d)**: This incorrectly changes the tense to Past Perfect.

**Rule**: For a negative sentence in the Past Continuous Tense, the passive structure is **Object + was/were + not + being + V3**. A common alternative is to make the object positive and use 'No' instead of 'not any'.

- **Correct Answer (b)**: The phrase 'not any progress' is converted to 'No progress', which becomes the subject. The verb form 'was being made' is the correct passive for the Past Continuous. This structure is more natural than 'Any progress was not being made'.
- **Incorrect Answer (a)**: This changes the tense to Simple Past.
- **Incorrect Answer (c)**: This changes the tense to Present Perfect.
- **Incorrect Answer (d)**: This is grammatically possible but less idiomatic than using 'No progress' as the subject.

**Rule**: For a negative sentence in the Past Continuous Tense, the passive voice structure is **Object + was/were + not + being + V3 + by + Subject**.

- **Correct Answer (c)**: The object 'the matter' becomes the subject. The passive verb form 'was not being taken' correctly reflects the negative Past Continuous tense.
- **Incorrect Answer (a)**: This incorrectly changes the tense to Simple Past.
- **Incorrect Answer (b)**: This incorrectly changes the tense to Present Perfect.
- **Incorrect Answer (d)**: This incorrectly changes the tense to Present Continuous.

**Rule**: Interrogative sentences in the Simple Past Tense starting with 'Who' are converted to passive voice using **By whom + was/were + object + V3?**

- **Correct Answer (c)**: 'Who' becomes 'By whom'. The object 'you' becomes the subject, which takes the plural verb 'were', followed by the past participle 'taught'. The infinitive phrase 'how to swim' remains.
- **Incorrect Answer (a)**: 'was' is incorrect with the pronoun 'you'.
- **Incorrect Answer (b)**: 'who' is the incorrect case; 'whom' is required after the preposition 'By'.
- **Incorrect Answer (d)**: This word order is awkward and not standard for this type of question.

**Rule**: For a Present Continuous Tense sentence, the passive structure is **Object + is/am/are + being + V3 + by + Subject**.

- **Correct Answer (d)**: The object 'the neighbors' becomes the subject. Since 'neighbors' is plural, 'are' is used, followed by 'being' and the past participle 'disturbed'.
- **Incorrect Answer (a)**: This incorrectly changes the tense to Simple Past.
- **Incorrect Answer (b)**: This incorrectly changes the tense to Simple Present.
- **Incorrect Answer (c)**: This incorrectly changes the tense to Present Perfect.

**Rule**: For an interrogative Present Continuous sentence with a phrasal verb starting with 'Who', the passive structure is **By whom + is/am/are + object + being + V3 + preposition?**

- **Correct Answer (a)**: 'Who' becomes 'By whom'. The object 'the door' is singular, so 'is' is used. This is followed by the object, 'being', the past participle 'knocked', and the preposition 'at' is correctly retained.
- **Incorrect Answer (b)**: This incorrectly changes the tense to Past Continuous.
- **Incorrect Answer (c)**: 'who' is the incorrect case; 'whom' is required after the preposition 'By'.
- **Incorrect Answer (d)**: This incorrectly changes the tense to Present Perfect.

**Rule**: A negative imperative sentence that gives advice can be converted to passive voice in several ways.

- **Correct Answer (d)**: All the options are valid passive constructions for the given imperative sentence.
- (a) **'Promises you can't keep should not be made'** uses the modal 'should' to convey the advice.
- (b) **'Let promises you can't keep not be made'** uses the 'Let' structure for negative commands/advice.
- (c) **'You are advised not to make promises you can't keep'** explicitly states that the sentence is advice.
Since all three are correct and appropriate, 'All of the above' is the best answer.