Question

key reinforcers of nicotine addiction to cigarettes include all of the following except
multiple choice
decreased heart rate.
a reduction in feelings of anxiety and depression.
nicotines ability to alleviate withdrawal symptoms.
increased dopamine levels in the brain.

Explanation:

Nicotine actually increases heart rate. It acts as a stimulant. The other options - reduction in anxiety/depression (nicotine can have a short - term calming effect for some, though it's a false comfort), alleviating withdrawal symptoms (as it's the substance being withdrawn), and increased dopamine levels (nicotine causes dopamine release which is related to the rewarding aspect of addiction) - are all key reinforcers of nicotine addiction.

Answer:

decreased heart rate.