Respuesta :
The ground(Earth's surface) is at low potential whereas the clouds are at higher potential. Due to this potential difference, we see lightning.
Answer: a.) lightning
Explanation:
Lightening is the discharge of electricity within the clouds, between the clouds or from cloud to ground. This occurs due the potential difference between the two regions.
A cloud is composed of condensed water vapors. The upper region of cloud is positively charged and lower region is negatively charged.This difference causes lightning to occur. sometimes we hear the thundering sound after lightning. This occurs when high temperature of the electric discharge breaks the air insulation and air expands.
Thus, lightning provides evidence of electric fields in the atmosphere