Question

The lowest region of the atmosphere is known as
A. Stratosphere
B. Ozonosphere
C. Troposphere
D. Mesosphere

Answer 1

Hint: The atmosphere is composed of many layers based on different temperatures. These layers are the stratosphere, troposphere, thermosphere, and mesosphere. The farther region is about five hundred kilometres above the earth’s surface and this is called the exosphere. This layer is the lowest layer of the atmosphere.

Complete answer:
The troposphere is the lowest layer of the earth’s atmosphere and the site of all-weather on earth. The troposphere is bound by a top layer of air called the tropopause, which separates the troposphere from the stratosphere. It comprises about 75% of the atmosphere's mass and 99% of the total mass of water vapour and aerosols. The planetary boundary layer is the lowest part of the troposphere, where friction with the Earth's surface influences the airflow. The temperature of the troposphere decreases as altitude increases.
a) Stratosphere: This is the second layer of the earth’s atmosphere from the above. The troposphere is right below the stratosphere. Above the stratosphere is the mesosphere.
b) Ozonosphere: Ozone is the shield that is the locale of the earth’s stratosphere which retains the major sun radiation (UV radiation). This is the part of the stratosphere that contains the concentrated O3 (trioxygen or ozone) which is sufficient to block the UV radiation from the sun.
c) Mesosphere: This is the layer of the atmosphere. The mesosphere is directly below the thermosphere and below the stratosphere. It extends from fifty kilometres to eighty-five kilometres above our planet.

Hence, the correct answer is option C.

Note: The atmosphere comprises layers based on temperature. The composition of gases in each layer is different. The different layers are placed at a certain position from the earth. The troposphere starts from the earth’s surface and goes up to seven to twenty kilometres above sea level. There are many kinds of clouds found in this region and the weather changes also occur in this area. It holds nearly all of the water vapour in the Earth's atmosphere regulates temperature and produces weather.