Answer:
B. 60°
Step-by-step explanation:
1. The measure of all angles in a triangle sum up to 180°. This means that y + y + 60 = 120.
2. (Solving)
Step 1: Simplify both sides of the equation.
Step 2: Subtract 60 from both sides.
Step 3: Divide both sides by 2.
Step 4: Check if solution is correct.
Therefore, the answer is B. 60°.