Jenny Has an IQ in the Average Range

Jenny has an IQ in the average range. However, at school she is doing very badly. She has consistently scored at 2 or more grade levels below the grade she is actually in. From this, a diagnostician would hypothesize that Jenny

A) most likely has mental retardation.
B) most likely has an anxiety disorder.
C) most likely does not have a learning disability because her IQ is only average.
D) most likely has a learning disability.