Provide the correct IUPAC names for the following compounds.

a) CH3CH2CH(C2H5)C(CH3)2CH2CH3

A) 3-Ethyl-2-methylhexane
B) 4-Ethyl-3-methylpentane
C) 2-Methyl-3-ethylpentane
D) 5-Ethyl-4-methylheptane