The ottoman empire grew and expanded after it conquered the
mughal empire.
byzantine empire.
gupta empire.
roman empire.

The correct answer is:  

Byzantine Empire.

The Byzantine-Ottoman wars led to the ultimate overthrow of the Byzantine Empire and eventually to the rise of the Ottoman Empire. After the Ottomans' captured Constantinople, they kept their conquests going across Europe and the Middle East until their power finally reached its peak in the mid 17th century.

formulating the initial idea for the policy

answer is c.