In a reflex arc what is the destination of neural impulses beginning in one of the ventral roots of the spinal cord

The destination is the effector.

Explanation:

he reflex arc is a type of reflex that is processed in the spinal cord,

and not in the brain. A stimulus arrives at the spine, it is processed there, and an answer is produced. Then the answer travels through the motor neurons to its final destination, which would be the effector. The effector can be a muscle or an organ, in other words, it is the place/part of the body that the motor neuron affects.

so what is your question?