Given that two charges are exactly the same size, let's find where the electric field strength will be zero.
We know the two charges are exactly the same size but we do not if they are like charges or unlike charges.
So, since we do not know if the charges have the same sign or are opposite charges, it is difficult to conclude where the electric field strength will equal zero.
Therefore, we can say there is not enough information to determine where the electric field strength will equal zero.
ANSWER:
B. Not enough info