B. The household could increase his total utility by consuming more of X and less of Y
C. The household could increase his total utility by consuming less of X and more of Y
D. Price of X is greater than price of Y
Explanation
If the household consumes along the budget constraint where MUx/Px > MUy/Py then assuming normal preferences, we are sure that the household could increase its total utility by consuming more of X and less of Y.