A Produce Vendor Sets Up a Stand Next to a Busy

A produce vendor sets up a stand next to a busy road,with a box for money and a sign that says $3 per bag.Most customers who take a bag of garden produce place $3 in the box.What is the most likely reason for this?

A) Most customers understand that this economic opportunity will continue to exist only if they are fair.
B) Most customers feel self-conscious in front of the others looking at the produce.
C) Most produce customers are more morally conscious than the average population.
D) Most customers are sensitive to the difficulties of produce gardening.