Which of the following are factors that might influence a person's political opinions?
a. living in a metropolitan area
b. working as a long-distance truck driver
c. being an expert in constitutional law
d. all of these can be considered factors.

D. All of these can be considered factors.
All of the above can be considered factors, as if a person is living in a metropolitan area, certain political decisions will affect their lives, such as transportation policies. If a candidate touches more on farming policy than lowering the fee for the subway, for example, they may want to choose a candidate who can relate more to them. The work a person does equally will help who they vote for or their political opinions as decisions based on jobs and work will affect their workplace. If a person has knowledge of constitutional law, they can apply this knowledge to better understand the politics going on around them and this can help shape different political opinion, if they see a situation clearer than someone who does not have previous knowledge.