Auroras occur in the
a. troposphere
b. stratosphere
c. mesosphere
d. thermosphere

Auroras occur in the "thermosphere".

The thermosphere lies between the exosphere and the mesosphere.It is a district of expanding temperature in Earth's climate that is situated over the mesosphere.  

The thermosphere significantly helps in ensuring the earth and making space investigation and present day types of correspondence conceivable. It additionally supports and ensures life on the planet. It reuses water, retains the sun's energy, and makes a moderate temperature.  

The aurora (Northern Lights and Southern Lights) generally present in the thermosphere. It is a  natural electrical marvel described by the presence of streamers of rosy or greenish light in the sky, particularly close to the northern or southern attractive shaft. The impact is caused by the communication of charged particles from the sun with iotas in the upper atmosphere.

characterization of nanoparticles is a critical step in nanomaterial production as it provides information of dimension, morphology, surface charge, distribution and degree of surface functionalization.

the dna of humans and mice is almost 92% similar. this similarity indicates that . mice have a tail, while humans have a tailbone. the tailbone is a structure in humans.yes it's true.