The Answer to this this question would be letter A
Answer:
serotonin
Explanation:
Here is the complete question:. on average, those with the short form of the ________ transporter gene and a history of stressful experiences reported more than average symptoms of depression.
Serotonin is sometimes called the happy chemical, because it contributes to wellbeing and happiness. The scientific name for serotonin is 5-hydroxytryptamine, or 5-HT.