In a typical medium speed, 4-stroke cycle diesel engine ______.

(a)    fuel injection starts at 10° before to dead center and ends at 20° after tor dead center
(b)    fuel injection starts at top dead center and ends at 20° after top dead center
(c)    fuel injection starts at just before top dead center and ends just after top dead center
(d)    may start and end anywhere
(e)    none of the above.

Ans: a