In the study of chlorination of propane, four prouducts A, B, C, and D of the formula `C_(3)H_(6)C1_(2)` were isloated. Each of then was further chlorinated to provide trichloro products, `C_(3)H_(5)C1_(3)` . It was found that A provided one trichloro product, B gave two, and C and D each gave three. What the structural of A, B, C, and D ?
A. `ClCH_(2)-C(Cl)_(2)-CH_(3)`
B. `CH_(3)-C(Cl)_(2)-CH_(3)`
C. `CH_(3)-CH_(2)-CHCl_(2)`
D. `CH_(3)CHClCH_(2)Cl`