Behaviorists such as john b. watson would have been least likely to attribute a child's behavior to:

I believe the answer is: mindless habits.

Behaviorists tend to believe that the behavior that displayed by individuals would alwaays be created as a response to a certain stimuli.
So, they tend to attribute a behavior to things such as parenting technique, the pressure that individuals get from their friends, etc.

True. r u cheating on a test. bro not cool.