The Khunjerab Pass, located at 4,693 meters in the Karakoram Range, is the primary border crossing between Pakistan and China. It is a key part of the Karakoram Highway, facilitating trade and connectivity under the China-Pakistan Economic Corridor (CPEC).

The Sino-Pakistan Boundary Agreement, signed on 2nd March 1963, demarcated the border between Pakistan and China in the Gilgit-Baltistan region. It strengthened bilateral ties and resolved territorial disputes, notably involving the Shaksgam Valley.

Pakistan's first constitution was adopted in 1956, which declared the country an Islamic republic; the other years correspond to independence and later constitutions.

The Constitution of the Islamic Republic of Pakistan is the highest law of the land, making option d correct.

The Supreme Court is the highest judicial body charged with constitutional interpretation, so option c is correct.

The WHO is the UN agency responsible for international public health and coordinating responses to disease outbreaks, making option d correct.

The G20 is chiefly a forum for international economic cooperation and policies to promote financial stability, so option c is correct.

PPPs leverage private capital and expertise while allocating some construction and operational risks to private partners, though public oversight remains necessary.

TOD concentrates mixed-use, higher-density development near transit nodes to increase public-transport use and reduce car dependence.

Mills' sociological imagination refers to linking personal troubles to public issues and understanding individuals within broader social contexts.