The real axis is a horizontal axis, and if it's located in above the horizontal axis, then its real part is positive -this leaves us with the option b) - the correct answer- since the real part of c) and d) is negative and would be below the x axis and the real part of a) is 0 and would be ON the x axis.
The correct answer for this question is this one: d) -1-2i " Any complex number with a negative real part and positive imaginary part. It has to be of this form, a+bi so that a<0 and b>0.
