The correct answer is: B. Isotherms.
Isotherms are lines on a map or chart that connect points of equal temperature. They are used to show the distribution of temperature in a region. Isotherms are typically drawn at regular intervals, such as every 10 degrees Celsius.
Isobars are lines on a map or chart that connect points of equal pressure. They are used to show the distribution of pressure in a region. Isobars are typically drawn at regular intervals, such as every 1 millibar.
Thermals are rising columns of warm air that form in the atmosphere. They are often visible as clouds. Thermals are important for aviation, as they can be used to gain altitude.
Thermographs are graphs that show the variation of temperature over time. They are used to study climate change and other weather patterns.
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