In a typical medium speed, 4-stroke cycle diesel engine ___________________?

In a typical medium speed, 4-stroke cycle diesel engine ___________________?

A. fuelinjection 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 deac center
D. may start and end anywhere
E. none of the above

For the same compression ratio_____________________?

For the same compression ratio_____________________?

A. Otto cycle is more efficient than the Diesel
B. Diesel cycle is more efficient’than Otto
C. both Otto and Diesel cycles are, equally efficient
D. compression ratio has nothing to do with efficiency
E. which is more efficient would depend on engine capacity