When an addict stops taking cocaine, the addict's body will not function normally until

narcotics are prescribed by a physician

it has undergone irreparable damage

the number of receptors in the affected synapses has had time to readjust

the amount of cocaine has been reduced to a safe level

Letter C

Explanation:

Some researchers propose that the changes may come from dopamine depletion, changes in neurotransmitter receptors or other structures, or changes in other brain messenger pathways that could cause the changes in mood, behavior, and cognitive function associated with chronic stimulant abuse.

Cocaine blockade of the dopamine reuptake transporter extends the availability of dopamine in the synaptic space where it continues to occupy the dopamine receptor and causes the postsynaptic neurons to fire for a longer than normal period. This extended firing of the postsynaptic neurons resulting from prolonged dopamine receptor activity is initially experienced subjectively by the cocaine user as a positive sensation involving increased energy, arousal, and stimulation. Cocaine-induced cognitive deficits can last up to 3 months after heavy use before baseline functioning is restored.