A monkey makes arm movements while you record the activity of a cell in primary motor cortex in a cortical column related to arm muscles.What is probably true about the cell's activity?

A)It is linearly related to movement direction and thus can predict the direction of the upcoming movement.
B)It does not vary with movement direction.
C)It always increases during the movement.
D)It is nonlinearly related to movement direction and does not predict the specific direction of the upcoming movement.