To determine whether a triangle with sides \( a = 16 \), \( b = 12 \), and \( c = 20 \) can be a right triangle, we can use the Converse of the Pythagorean Theorem. The theorem states that if \( c \) is the longest side of a triangle, then the triangle is a right triangle if and only if \( a^2 + b^2 = c^2 \).
Let's calculate:
- \( a^2 = 16^2 = 256 \)
- \( b^2 = 12^2 = 144 \)
- \( c^2 = 20^2 = 400 \)
Now, we check if \( a^2 + b^2 = c^2 \):
\[ 256 + 144 = 400 \]
Since \( 400 = 400 \), the equation holds true.
Therefore, the answer is:
Option A: Yes, a right triangle can be formed.