The Students of Holly Oak Academy Always Got Low Grades

The students of Holly Oak Academy always got low grades in mathematics.The management looked into the matter and found out that though the handouts given by the professor were extremely good,the professor was unable to convey the steps and procedures involved.This is because the professor had _____.

A) low ability of written comprehension and high ability of oral comprehension
B) low ability of written expression and high ability of oral expression
C) high ability of written expression and low ability of oral expression
D) high ability of written comprehension and low ability of oral comprehension
E) high ability of written comprehension and high ability of oral comprehension