question_answer

Consider the following statements: Knock in the SI engine can be reduced by

1. Supercharging

2. Retarding the spark.

3. Using a fuel of long straight chain structure.

4. Increasing the engine speed.

Of these statement:

A) 1 and 2 are correct  

B) 2 and 3 are correct

C) 1, 3 and 4 are correct

D) 2 and 4 are correct