大全670，请教NN，为何C不行，多谢

12.   Stars like the sun can continue to shine steadily for billions of years because its light and heat are produced by nuclear fusion, in which titanic releases of energy result in the loss of only tiny amounts of mass.

(A) its light and heat are produced by nuclear fusion, in which

(B) nuclear fusion produces its light and heat, in which

(C) nuclear fusion produces their light and heat, where

(D) its light and heat are produced by nuclear fusion, where（E）

(E) their light and heat are produced by nuclear fusion, in which

why not C, what's the difference between "in which" and "where"? many thx!

在GMAT里面where我只见过指地点的，其他的指代我没有见过.

而却C里面where要修饰也是修饰heat，因为它是定语从句。