Which lines are drawn on map to join places equal in terms of the time taken to reach them ?

Isochrone

The correct answer is Option 3: Isochrone

Isochrone lines are drawn on a map to join places equal in terms of the time taken to reach them.

Other Options:

Option 1: Isobars : isobars are lines joining places having equal atmospheric pressure.

Option 2: Isotherms : isotherms are lines joining places having equal temperature.

Option 4: Isoneph : isonephs are lines joining places having equal cloud cover.