Concluding that a hypothesis must be true because it adequately accounts for the explanandum commits which of the following fallacies?

A) division
B) appeal to majority
C) undistributed middle
D) affirming the consequent
E) denying the antecedent

Concluding that a hypothesis must be true because it adequately accounts for the explanandum is a form of affirming the consequent. This fallacy occurs when someone assumes that if a hypothesis is true, then its predicted consequences must also be true. However, just because a hypothesis accounts for the observed data (explanandum), it does not necessarily mean that it is the only possible explanation or that it is true.