The correct decreasing order of calorific values is
A. `C_(2)H_(2)gtC_(4)H_(10)gtC_(3)H_(8)gtC_(2)H_(4)`
B. `C_(4)H_(10)gtC_(3)H_(8)gtC_(2)H_(4)gtC_(2)H_(2)`
C. `C_(2)H_(4)gtC_(3)H_(8)gtC_(4)H_(10)gtC_(2)H_(2)`
D. `C_(3)H_(8)gtC_(2)H_(4)gtC_(4)H_(10)gtC_(2)H_(2)`