What happens to ATP production in a cell when its mitochondrial complex II becomes dysfunctional?

a More ATP production due to increased conversion of succinate to fumarate b Less ATP production due to increased conversion of succinate to fumarate c Absence of ATP production due to increased conversion of succinate to fumarate d More ATP production due to decreased conversion of succinate to fumarate e Less ATP production due to decreased conversion of succinate to fumarate