One sine wave has a positive peak at 75⁰, and another has a positive peak at 100⁰. How much is first sine wave shifted in phase from the 0⁰ reference?

• A. leads reference angle by 10⁰
• B. lags reference angle by 10⁰
• C. leads reference angle by 15⁰
• D. lags reference angle by 15⁰