Many plants respond to the days growing shorter in the fall by going dormant, and after the autumnal equinox, days gradually shorten in the Northern Hemisphere. Given these facts, many plants go dormant during the   among the following options:
- heat or cold
 - earth's revolving
 - autumnal equinox
 - colder and wetter
 - It helps them survive
 - cloudy and rainy weather
 - Plant growth is reduced
 - fire conditions


 

   autumnal equinox      