Two identical electric dipoles, each consisting of charges $-q$ and $+q$ separated by distance d, are arranged in x-y plane such that their negative charges lie at the origin O and positive charges lie at points (d, 0) and (0, d) respectively. The net dipole moment of the system is : (A) $-qd$\hat{i} + \hat{j}$$ (B) $qd$\hat{i} + \hat{j}$$ (C) $qd$\hat{i} - \hat{j}$$ (D) $qd$\hat{j} - \hat{i}$$