Cold fronts cause thunderstorms as they pass by, and if cold air replaces warm air, it is called a cold front. Given these facts, what does cold air replacing warm air cause among the following options:
- Greenhouse gases
 - Pollution
 - Dehydration
 - thunderstorms
 - steady barometer readings
 - hypothyroidism
 - constant air pressure
 - stagnant air temperature


 

    thunderstorms     