The Exponents of a Cobb-Douglas Utility Function,U = C ^$\alpha$ M ^$\alpha$

The exponents of a Cobb-Douglas utility function,U = C ^$\alpha$ M ^{$\alpha$ -1},represent:

A) the share of income devoted to that good.
B) the rate at which a consumer can trade one good for the other.
C) the quantity of each good that is demanded.
D) the amount of utility each good provides.