Given the sign shown, is it mandatory to stop to allow a vehicle travelling in the opposite direction to pass?

A)No, because the sign grants right of way.
B)No, because the sign does not affect right of way.
C)Yes, as long as it is not possible to continue without forcing vehicles travelling in the opposite direction to stop.Correct
The sign in the question indicates a prohibition on entering a narrow passage unless it is possible to cross it without forcing vehicles travelling in the opposite direction to stop. Vehicles travelling in the opposite direction will encounter the next sign, which gives them right of way.