Consider the following statements:
(A) Propanal and Propanone are functional isomers.
(B) Ethoxyethane and methoxypropane are metameres.
(C) But-2-ene shows optical isomerism.
(D) But-1-ene and But-2-ene are functional isomers.
(E) Pentane and 2, 2-dimethylpropane are chain isomers.
In the light of the above statements, choose the correct option.