The highest elevation on this topographic map can be no more than about:
Contour lines are the lines joining points of equal height above or below sea level.
Contour interval is the vertical distance between the two contour lines which are next to each other.
In the above figure contour interval is 5 meters and sea level is taken as 0 elevation. Starting from the sea level as we go up there are there 6 contour lines.
6(contour lines) * 5(interval) =30
Thus the highest elevation on this topographic map can be no more than 34 according to the options given