Which One of the Following Students Is Attributing Success or Failure

Which one of the following students is attributing success or failure on a geology test to an internal source and thinks the cause is unstable and controllable?

A) Jane says she failed the test because it was too difficult.
B) Emily says she did well on the test because she is smart in science
C) Joe says he did well on the test because he studied hard.
D) Drew says he studied hard, but he failed because he is just not good in geology.