Answer:
A) (3,6)
Step-by-step explanation:
Let M be the midpoint of the line segment at (1,7) and (5,5). Then:
[tex]\mathsf{M\left(\dfrac{1+5}{2},\dfrac{7+5}{2}\right)}=\\=\mathsf{M\left(\dfrac{6}{2},\dfrac{12}{2}\right)}=\\=\mathsf{M\left(3,\,6\right)}[/tex]