Efficiency of general AM signal with em = E1 cos 1t + E2 cos 2t with modulation index m1 and m2 is __________ .

• A. <img src="/_files/images/electronics-and-communication-engineering/exam-question-papers/2-757-52-1.png">
• B. <img src="/_files/images/electronics-and-communication-engineering/exam-question-papers/2-757-52-2.png">
• C. <img src="/_files/images/electronics-and-communication-engineering/exam-question-papers/2-757-52-3.png">
• D. <img src="/_files/images/electronics-and-communication-engineering/exam-question-papers/2-757-52-4.png">