[单选题]
Electric dipoles always consist of two cl pt/wx 3/w wvi;ht9bdee-i01harges that auxi uq okvtsric .b(zp:7497: re
A. equal in magnitude; opposite in sign.
B. equal in magnitude; both are negative.
C. equal in magnitude; both are positive.
D. unequal in magnitude; opposite in sign.