Why are lists considered one$-$dimensional when they can contain data frames $($which are two$-$dimensional$)$ within them?

Question $10$Select one:

a$.$

Data frames are $$flattened$$ to spread the elements into a one dimensional object.

b$.$

We ignore the second dimension associated with data frames when they are put into a list.

c$.$

Each element of a list can be any R object but we associate a one$-$dimensional ordering with these elements.