LaKeisha stepped on a piece of glass and quickly pulled her foot away from that sharp object. Which of the following are responsible for sending a message to the muscles in LaKeisha's foot, resulting in her pulling her foot away from the piece of glass?

It is a motor reflex response

Explanation:

This motor reflex is carried out by motor neurons which are located in the Brain and spinal cord. They are of two types, the upper motor neuron and the lower motor neuron. They upper motor neuron connects with the lower motor neuron in the transmission of impulses. Their presynaptic tract is in the cerebral motor area via the corticospinal tract while their post synaptic tract is in muscle fibres. Thus when she hit her legs on the glass, afferent fires was sent to the brain which then sent efferent impulses to the muscle fibers to quickly withdraw the leg due to action of motor neurons.

For the Central Nervous system  and different organs of the body  to be in constant touch with the immediate environments,Sensory inputs must be sent   from group of sensitive cells  located under the skin in all mammals and special cells in other organism. These are called receptors. in this scenario they are exteroreceptos because the stimulus is the piece of glass .The  changes/ stimulus detected by these receptors are carried  as input by   group of neurons called sensory  or afferent Neurons,  as  action potential to the  brain, via the spinal cord.

The   cell body  of  sensory neuron is located in the spinal cord so that they can synapse with the interneurons, which send the input to the  brain and the response from the brain ( outputs)return through another neuron type called motor neuron to the effectors (muscles  in her legs ) for her to pull her leg away.This pathway  which start with receptors ans ends with effectors is  called Reflex arc.