Friends, family members, role models, and society are all examples of that can affect your decisions about drugs.
a. economic influences
b. internal influences
c. private influences
d. external influences

Friends, family members, role models, and society are all examples of "external influences" that can affect your decisions about drugs.

We settle on an inconceivable measure of decisions consistently. From little choices about what to wear, to expansive choices that influence our fates – both by and by and professionally.  

In our decision making we are affected by a mind blowing measure of external factors. Some of the time this is something to be thankful for in light of the fact that it gives us the data expected to settle on a good choice. Different occasions it can befuddle and hinder precise appraisals.