How many conductors in RS-485 cable?

[tylerfini3]

In a communications system, how many conductors would you expect to find in an RS-485 cable not including the foil shield?

On the figure I cannot paste it shows a half duplex and a full duplex.
Half duplex looks to have 2 conductors
Full duplex shows 4.
What would the answer be?
It does say half duplex are the most common.

[copes2680]

In a communications system, how many conductors would you expect to find in an RS-485 cable not including the foil shield?

On the figure I cannot paste it shows a half duplex and a full duplex.
Half duplex looks to have 2 conductors
Full duplex shows 4.
What would the answer be?
It does say half duplex are the most common.

This question was on the NETA IV practice exam as well. The answer that was correct for me was 2. I would assume that is because that is the most common.

[testguy]

This question has been updated with new versions to reflect both half- and full-duplex communication for better clarity. We also added another question regarding which type is most common.