The following question refers to this figure of a simple metabolic pathway:

-A mutation results in a defective enzyme A. Which of the following would be a consequence of that mutation?

A) an accumulation of A and no production of B and C
B) an accumulation of A and B and no production of C
C) an accumulation of B and no production of A and C
D) an accumulation of B and C and no production of A
E) an accumulation of C and no production of A and B