A triangle can be formed with side lengths 4 in, 5 in, and 8 in.

a. True

b. False

Triangle Inequality:

The sum of the length of any two sides of a triangle must be greater than the length of the third side.

4 + 5 = 9 > 8 Check

4 + 8 = 12 > 5 Check

5 + 8 = 13 > 4 Check

All three combinations prove true, therefore the correct answer is A) True.