Three point charges +q, -2q and +q are placed at points (x = 0, y = a, z = 0), (x = 0, y = 0, z = 0) and (x = a, y = 0, z = 0) respectively. The magnitude and direction of the electric dipole moment vector of this charge assembly are
1
qa along the line joining points (x = 0, y = 0, z = 0) and (x = a, y = a, z = 0)
2
√2qa along the line joining points (x = 0, y = 0, z = 0) and (x = a, y = a, z = 0)
3
√2qa along +x direction
4
√2qa along +y direction