To know which forms a triangle, we have to use Pythagorean's Theorem.
[tex]\begin{gathered} 5^2=3^2+4^2 \\ 25=9+16 \\ 25=25 \end{gathered}[/tex]
Option A forms a right triangle.
[tex]\begin{gathered} 9^2=7^2+8^2 \\ 81=49+64 \\ 81=113 \end{gathered}[/tex]
Option B doesn't form a right triangle.
[tex]\begin{gathered} (\sqrt[]{95})^2=9^2+3^2 \\ 95=81+9 \\ 95=90 \end{gathered}[/tex]
Option C doesn't form a right triangle.
Hence, the answer is A.
