单选题The majority of medium speed and high speed marine diesel engines for main or auxiliary drive operate on the （） cycle.Atwo-strokeBfour-stokeClong-strokeDshort-stroke
单选题
The majority of medium speed and high speed marine diesel engines for main or auxiliary drive operate on the （） cycle.
A
two-stroke
B
four-stoke
C
long-stroke
D
short-stroke
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