Answer
a) The compounds that can be Alkanes are:
compound c: $C_{14}H_{30}$
b) The compounds that can be cycloalakanes are:
compound B $C_{5}H_{10}$
Work Step by Step
Compound A is an alkene. It cannot be a cyclocompund as it consists of 2 carbons only.
Compound B can be either a cycloalkane or alkene as they have the same formula $C_{n}H_{2n}$
Compound C is an alkane as its formula is $C_{n}H_{2n+2}$
Compound D is neither an alkane nor a cycloalkane.
