The reaction conditions leading to the best yield of `C_(2)H_(5)Cl` are
A. `C_(2)H_(6) ("excess")+ Cl_(2) overset("Uv light")(to)`
B. `C_(2)H_(6)+Cl_(2) ("excess")overset("UV light")underset("room temperature")(to)`
C. `C_(2)H_(6)+Cl_(2) ("excess") overset("UV light")(to)`
D. `C_(2)H_(6)+Cl_(2)overset("UV light")(to)`