Final answer:
Muhammad Ali was Egypt's leader responsible for its modernization and growth of the empire through reforms and initiatives in various sectors.
Step-by-step explanation:
The leader responsible for Egypt's modernization and growth of the empire was Muhammad Ali. During his rule, he implemented various reforms and initiatives to modernize Egypt. He encouraged cotton cultivation, established educational and medical colleges, built industrial infrastructure, and strengthened the military. Muhammad Ali's efforts significantly transformed Egypt and propelled its growth.