Explanation:

- Option 1: Zulfikar Ali Bhutto

- He was a prominent politician and later became the Prime Minister of Pakistan. He served as President briefly, but he was not the first.

- Option 2: Yahya Khan

- Yahya Khan was a military ruler and served as President later. He is known for his role during the separation of East Pakistan.

- Option 3: Iskander Mirza

- Iskander Mirza was indeed the first President of Pakistan, serving from 1956 until he was ousted in 1958.

- Option 4: Ayub Khan

- Ayub Khan was a military leader who succeeded Mirza and became the second President. He imposed martial law after ascending to presidency.

- Correct Answer: Iskander Mirza