Question

What is the lower layer of the atmosphere called?
A) ionosphere
B) Mesosphere
C) Troposphere
D) Stratosphere

Answer 1

Hint:The atmosphere is the layer of gases that surrounds the earth including the air we all breathe. It has several layers starting from the ground and stretching all the way to space.

Complete answer:Layers of the atmosphere are as below:
1) Troposphere
2) Stratosphere
3) Mesosphere
4) Thermosphere
5) Exosphere
Troposphere: It is the first layer of the atmosphere and it is also the one where we all live, it extends from the earth's surface to about $10Km$ in the sky. This layer traps the sun’s heat as a result warm or cool weather comes. Hot air balloons fly in this layer only.
Stratosphere: It is the layer above the troposphere and it extends from the tropopause (area separating stratosphere and troposphere) to about $50km$up containing about $20\% $ of the earth gas, the ozone layer is also found in this layer only which protects us from the harmful radiation from the sun.
The top part of the stratosphere is hottest because the ozone layer generates a lot of heat, airplane and jet aircraft fly in this layer
Mesosphere: It extends from the stratosphere to approximately $93km$ high. It is the coldest layer of the atmosphere about $ - {130^ \circ }F$ near the top, This is the part where most of the meteors burn up.
Thermosphere: it is the layer above the mesosphere and this layer expands to approx. $500km$, It is very hot as the temperature can reach up to ${5000^ \circ }F$, This is because the air in the thermosphere consumes a lot of solar radiation. Most of the X-Ray and UV rays from the sun are consumed in this layer.
Exosphere: this is the last layer of the atmosphere.
So the correct answer is an option (A).

Note: Greenhouse effect is something that we have come across several times, in simple terms it is similar to the phenomena that occur in the greenhouse.
Just like in a greenhouse, our earth absorbs the radiation but is not able to radiate it hence trapped in the earth’s atmosphere and increasing the temperature of the whole earth.