(a) Two

(b) Five

(c) Three

(d) Four

Solution:

Option (b) is the answer.

Neopentane, commonly known as 2,2-dimethylpropane, is a five-carbon double-branched-chain alkane. At room temperature and pressure, neopentane is a flammable gas that can condense into a highly volatile liquid on a cold day, in an ice bath, or when compressed to a higher pressure.