Answer: which
Explanation: I don't know how to explain this. It's just grammar.
Let's go through each answer.
A.
This is incorrect because it's a <span>measurement </span>not a direct object.
B.
This is also incorrect for the same reason, it's a measurement, not a direct object. :)
C.
This is correct because it's an object. :)
The answer is C.
Hope this helped! If you have anymore questions or don't understand, please comment on my profile or DM me. :)
C. 1200, cunquearen, from Old French conquerre "conquer<span>, defeat, vanquish," from Vulgar Latin *conquaerere (for Latin conquirere) "to search for, procure by effort, win," from Latin com-, intensive prefix (see com-), + quaerere "to seek, gain" (see query (v. )).</span>
