After the secession of East Pakistan, who became the head of government in Pakistan?

After the secession of East Pakistan, who became the head of government in Pakistan?

مشرقی پاکستان کے علیحدگی کے بعد ، پاکستان میں حکومت کے سربراہ کون بنے؟
Explanation

After the secession of East Pakistan in December 1971, General Yahya Khan resigned, and Zulfiqar Ali Bhutto became the President and later Prime Minister.

He assumed power on 20 December 1971 and began rebuilding Pakistan politically and economically.