What is the benefit and risk making voting mandatory in the unied states

I believe that the benefit may be that the candidate(s) would be more accurately elected because every citizen would have exercised his/her rights and selected the most worthy candidate. However, I think the risk could be great as well. For example, many legal voters are uninformed, and this could lead to uninformed voters choosing a careless candidate. This is due to the fact that he/she would be mandated to vote.

The answer is the letter c