Which complex number lies below the real axis and to the right of the imaginary axis?

The answer is
a. 3-i

The real axis is the horizontal axis and the imaginary axis is the vertical axis.
Therefore, the complex number 3-i can be found 3 units to the right of the imaginary axis and -1 units from the real axis. A negative value means it's below the real axis.

The coordinates of point a right now is (-3,-1) you have to multiply these coordinates by a factor of 2 to get (-6,-2)