How are liquid rocket engines classified on the basis of their feed system?

A)
Boosting or auxiliary
B)
Single flight or reusable
C)
Restartable or single fired
D)
Pressurized or turbopump

Correct Answer :   Pressurized or turbopump


Explanation : Feed system is used for the transfer of the liquid propellants from their storage tank to the thrust chamber of the rocket engine. They can be a gas-pressurized feed system or turbo pump feed system.