Consider the following statements in respect of a C.I. engine.
1. An increase in compression ratio reduces the delay period.
2. An increase in injection advance angle increases the delay period.
3. An increase in jacket water temperature reduces delay period.
Which of the statements given above are correct?
(a) 1 and 2 only (b) 2 and 3 only
(c) 1 and 3 only (d) 1, 2 and 3