Answer:
B. 3
Explanation:
Since you are given that chord AB's length is 8 and is bisected by segment XC, that means segment BC's length is 4 and ∠XCB is a right angle. From there, we use Pythagorean Theorem to solve for length XC:
4² + b² = 5² (Or remember 3-4-5 makes a Pythagorean triple)
c = √(5²-4²)
c = 3