What is true about an electric motor? a. every half-turn of a current carrying wire the current is reduced causing it to spin. b. the current carrying loop is able to turn because the magnetic force is always at a right angle to it. c. the current carrying loop is able to turn because the magnetic force is always parallel to it. d. a and b.

The statement (C) The current carrying loop is able to turn because the magnetic force is always parallel to it.
In an electric motor the current do not reduce at any point. So, the (A) is also not correct.

The correct statement about an electric motor is (B), 
The current carrying loop is able to turn because the magnetic force is always at a right angle to it.