Answer:
Independent Variable: Give one group the drug and dont give the other group the drug
Dependent Variable:The data of if the drug improves the rats memory(if their memory is better, the same, or made worse)
Dopamine is a chemical released by neurons to send signals to other nerve cells. the brain includes several distinct dopamine pathways, one of which plays a major role in reward motivated behavior.
smoking is a habit, in a habit there is the cue, routine, and reward. with smoking the cue can be different things, most commonly stress or anxiety. the routine how you react to those cues, the reward is the chemical 'triggers' that are pulled inside you're brain leaving you feeling calm, happy, or relieved, etc.
The right choice would be A
Have very few or no predators in the new ecosystem.
