Interpole flux should be sufficient to
(a) neutralise the commutating self induced e.m.f.
(b) neutralise the armature reaction flux(c) neutralise both the armature reaction flux as well as commutating e.m.f. induced in thecoilD.C. generator generally preferred for charging automobile batteries is(a) series generator(b) shunt generator
(c) long shunt compound generator(d) any of'the above