Dave Consumes Two Normal Goods,X and Y,and Is Currently at an Optimum.If

Multiple Choice

Dave consumes two normal goods,X and Y,and is currently at an optimum.If the price of good X falls,we can predict with certainty that

A) Dave will definitely consume more of both goods since his real income has risen.
B) the substitution effect will be positive for good X and negative for good Y.
C) may consume more or less of good X and he will definitely consume less of good Y.
D) the substitution effect will offset the income effect for good X.