Correct option is A
Information Booster:
Qutb-ud-din Aibak, a former slave and trusted general of Muhammad Ghori, was appointed as the Viceroy of Indian territories by Ghori. As a sign of honor and authority, Muhammad Ghori bestowed upon Aibak the title of "Malik".
"Malik" means king or chieftain, used for high-ranking officials under a sovereign.
He was not titled Sultan during Ghori's lifetime because the title of Sultan was reserved for a sovereign ruler.
Aibak only declared himself Sultan after the death of Muhammad Ghori in 1206 CE, when he became the independent ruler and laid the foundation of the Delhi Sultanate.