In lap winding, the number of brushes is always

Double the number of poles
Same as the number of poles
Half the number of poles
Two

The correct answer is: B. Same as the number of poles.

In lap winding, the number of brushes is always the same as the number of poles. This is because the brushes are used to collect the current from the rotating armature of the motor. The number of brushes must be equal to the number of poles in order to ensure that the current is collected evenly from the armature.

Option A is incorrect because the number of brushes is not always double the number of poles. For example, a four-pole motor would have four brushes, not eight.

Option C is incorrect because the number of brushes is not always half the number of poles. For example, a four-pole motor would have four brushes, not two.

Option D is incorrect because the number of brushes is not always two. For example, a four-pole motor would have four brushes, not two.