Fill in the blank with an appropriate Preposition. Alexander profited…

The correct answer is Option (3) → by

Complete sentence: Alexander profited by the dissensions of the Rajas of Punjab. Alexander gained an advantage from the quarrels among the Rajas of Punjab.

Option	Used to show	Example
(1) for	purpose or benefit ("work for money"). "Profit for" does not name the source of the gain.	He worked hard for his family.
(2) with	company or the instrument used ("cut with a knife"). "Profit with" is not used.	She cut the cake with a knife.
(3) by (answer)	To profit by (or profit from) something is to gain an advantage from it.	A wise man profits by the mistakes of others.
(4) of	belonging or a part ("the king of Persia"). The verb "profit" does not take "of".	He is the captain of the team.