ANSWER
The midpoint is a) (m,n)
EXPLANATION
The point O has coordinate (0,0) and the point A has coordinate (2m,2n)
The x-coordinate of the midpoint is
[tex]x = \frac{0 + 2m}{2} [/tex]
[tex]x = \frac{2m}{2} [/tex]
[tex]x = m[/tex]
Also,
[tex]y = \frac{0 + 2n}{2} [/tex]
[tex]y = \frac{ 2n}{2} [/tex]
[tex]y = n[/tex]
The answer is A
