Explanation:

- The total number of students in sections A and B combined is \(40 + 60 = 100\).

- The total physics score of section A is \(40 \times 35 = 1400\).

- The combined average score for sections A and B is 50, so the total score for 100 students is \(100 \times 50 = 5000\).

- Since the total score from section A is 1400, the score from section B is \(5000 - 1400 = 3600\).

- Therefore, the average score for section B is \(\frac{3600}{60} = 60\).

- Option 3: 60 is indeed correct.