In a d.c. machine, the armature mmf is
(A) stationary w.r.t. armature. (B) rotating w.r.t. field.
(C) stationary w.r.t. field. (D) rotating w.r.t. brushes.
(A) stationary w.r.t. armature. (B) rotating w.r.t. field.
(C) stationary w.r.t. field. (D) rotating w.r.t. brushes.