F=ma 2015 Problem 13

The following information applies to questions 12 and 13}
A pendulum consists of a small bob of mass m attached to a fixed point by a string of length L. The pendulum bob swings down from rest from an initial angle \theta_{\max }<90 degrees.

Consider the pendulum bob when it is at an angle \theta=\frac{1}{2} \theta_{\max } on the way up (moving toward \theta_{\max } ). What is the direction of the acceleration vector?

Answer Choices
A. fma2015q13
B. nan
C. nan
D. nan
E. nan