Since 2010, a Conservative Organization Based in Florida Has Been

Since 2010, a conservative organization based in Florida has been pushing, and won support from legislatures in more than half the states, for a national convention of the states in order to pass a balanced budget amendment, and possibly others.This would be unusual in American history, if successful, because:

A) it would likely lead to the creation of an entirely new constitution.
B) the one time a national convention was held, no proposed amendments won passage.
C) no amendment has ever been passed through a national convention.
D) Americans have come to see amendments as requiring democratic approval in the states.