Equilibrium of third charge

Question

Mid way between the two equal and similar charges, we placed the third equal and similar charge.
Which of the following statements is correct, concerned to the equilibrium along the line joining the
charges ?
(A) The third charge experienced a net force inclined to the line joining the charges
(B) The third charge is in stable equilibrium
(C) The third charge is in unstable equilibrium
(D) The third charge experiences a net force perpendicular to the line joining the charges

Answer 1

Answer will be (B) The third charge is in stable equilibrium. 

Answer 2

b)The third charge is in stable equilibrium

The repulsive forces on the 3rd charge due to 1^st and the 2^nd charges are equal in magnitude and are directed in the opposite direction to each other. Hence, the effect of these forces on the 3rd charge cancels out and it remains in stable equilibrium.