Step 1: Recall the fact:
Portrait painting reached its peak in the Mughal court during the rule of Jahangir. He loved realistic study of faces, animals and birds.
Step 2: Check the options:
Artists like Ustad Mansur and Bishandas worked in his court and painted fine portraits. So (A) is correct.
(B) Humayun: his period saw the start of Mughal painting under Persian masters, not the peak of portraits.
(C) Akbar: his time is known for large illustrated books and group scenes.
(D) Shah Jahan: his period is known for rich finish and grand court scenes.
Final Answer:
(A) Jahangir