Which One of the Following Girls Is Most Likely to Attribute

Which one of the following girls is most likely to attribute a low exam grade to an external cause?

A) Anna's teacher encourages her to seek his help if she needs it.
B) Betsy knows that other students in her class all did well on the exam.
C) Carol has gotten low grades on most previous exams.
D) Donna thought she knew the material even though she really didn't.