[单选题]
Electric dipoles always consisq/xy ru; 7kjq/ -cci-)nj d/bgt s01 uc i+-e )f jb1vpqol6q-axof two charges that are
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.
