Option 1 -> Isotherm: Lines connecting points of equal temperature on a map.
Option 2 -> Isobar: Lines connecting points of equal atmospheric pressure on a map.
Option 3 -> Isobaths: Lines connecting points of equal depth, typically used in bathymetric (underwater) maps.
Option 4 -> Isohyets: Lines connecting points of equal rainfall or precipitation.
Hence, Isobar -> Isobars are the standard meteorological tool used on weather maps to show pressure systems, helping identify high and low-pressure areas that determine weather patterns and wind direction -> correct