[单选题]
A heat engine absorbs 64 kcal of heat each cyclk0/iu z:dcwa8 zw:z z9e and exhausts 42 kcalg(5v 72:uwq0 z3nipdp qoe 0ed. Calculate the work done each cycl:p7 w5iug3(oqevezndp q02 d0e.
A. $22 \; kcal$
B. $42 \; kcal$
C. $64 \; kcal$
D. $106 \; kcal$