For a right triangle, according to Pythagorus theorem,
[tex]c^2=a^2+b^2[/tex]Here, c is the hypotenuse, a, b- length of other two sides.
The longer side is called the hypotenuse of a right triangle.
Conside option 1
1.6, 6.3, 6.5
6.5 is the longest side.
[tex]\begin{gathered} 6.5^2=42.25 \\ 6.3^2+1.6^2=42.25 \\ 6.5^2=6.3^2+1.6^2 \end{gathered}[/tex]Since side lengths 1.6, 6.3, 6.5 obeys Pythagorus theorem, the sides is of a right triangle.
The other given ste of sides does not follow Pythagorus theorem.
Consider 1.1, 6.3 , 6.5
[tex]6.5^2\ne1.1^2+6.3^2[/tex]Consider 4, 5, 6.
[tex]6^2\ne4^2+5^2[/tex]Consider 1.7, 14.4. 43.3.
[tex]43.3^2\ne14.4^2+1.7^2[/tex]Hence, 1.6, 6.3, 6.5 is correct.