Examine the air pressure map. Which type of line is shown on the map?

The correct answer is Isobar.
Isobars are lines that connect points of equal atmospheric pressure on weathers maps. They are drawn in such a way that they never cross each other. They are used by meteorologists to depict atmospheric pressure changes over a particular area and to make predictions about the wind flow ( changing directions of wind).
The isobars are generated from mean sea level pressure reports and the pressure values are given in millibars.