C, because the mountain cannot actually hold things.
The answer should be "slow" the first pairing both end in "-est" making them superlatives giving a parallel in the structure. Following the same structure, the words from the pairing after can be ignored, the word dim is an adjective, "light" bulb is a noun, therefore, it is not a parallel structure.
Animals , Plants , Bacteria
A is the correct answer, because it is grammatically correct and the noun/verb agrees.