In a Simple Equilibrium a + B C, Will

In a simple equilibrium A + B C, will there be any stress to the system if both B and C are added to the equilibrium system simultaneously and in the same amount?

A) No, these two stresses will always cancel each other out.
B) No, these two stresses will cancel each other out unless the initial concentrations of B and C are also the same.
C) Yes, the same amount of A is also required for the stresses to cancel each other out.
D) Yes, unless the initial concentrations of B and C are also the same.
E) More than two of the above statements are correct.