This bag of rice is __ heavier than that one. A much B more C very please help me to answer and explain the reason!

This bag of rice is __ heavier than that one. A much B more C very please help me to answer and explain the reason!

A multiple modifies the comparative order
More is not available. It is a comparative level in itself and can be modified countably
Very itself is a grammatical error when used in a sentence