Question

Direct current, DC, flows in a _________ direction while alternating current, AC, the direction of flow ___________.
Responses
A single, is unidirectionalsingle, is unidirectional
B constant, periodically reversesconstant, periodically reverses
C opposite direction, is multipleopposite direction, is multiple
D periodically reversing, is constant

Answer 1

The correct response is:

B. constant, periodically reverses

So the complete sentence would be: "Direct current, DC, flows in a constant direction while alternating current, AC, the direction of flow periodically reverses."