Explanation:

- The candidate answers in a cycle: A, B, C, D, A, B, C, D, and so on.

- Every cycle of 4 questions, option C is chosen correctly once, which fetches 4 marks.

- The other three questions in the cycle are answered incorrectly, losing 1 mark each.

- Each cycle, therefore, yields: 4 - 3 = 1 mark in total.

- For 50 questions, calculate the total cycles: 50/4 = 12 full cycles and a remainder of 2 questions.

- In 12 full cycles, the score is: 12 times 1 = 12

- The remaining 2 questions will be answered as A and B, both wrong, reducing the score by 2.

- Total score: 12 - 2 = 10.

Correct Answer: Option 3: 10