To pay at a toll booth, you must pass...

A)through the lane indicated by the red cross.
B)through any lane, indistinctly.
C)through the lane indicated by the green arrow.Correct
At a toll booth, you must follow specific signage instructions for each lane. The green arrow indicates the lane enabled and available for passage and toll payment. The red cross, on the contrary, indicates a closed or unavailable lane that you must not use.