The state transportation department wants to find out how citizens of the state would feel about increasing fees on the state's toll roads.

which surveying technique is most likely to give an unbiased report of the citizens' opinions?

a) survey a random selection of drivers a passing through the state's highway toll booths.

b) survey a random selection of truck drivers who use the state's toll roads.

c) survey a random selection from a list of the state's citizens.

d) survey a random selection of members of the state's transportation department.