Lowermost layer of Atmosphere is?ATroposphereBStratosphereCThermosphereDNone of the aboveAnswer: A. Troposphere Read Explanation: Troposphere The Troposphere is the lowest layer of Earth's atmosphereIt extending from the surface up to an average altitude of 12 kilometers (7.5 miles)It contains approximately 75-80% of the atmosphere's total mass and 99% of its water vaporCharacteristics of Troposphere Temperature: Decreases with altitude.Pressure: Decreases with altitude. Humidity: High, with most atmospheric water vapor.Weather: Almost all weather phenomena occur here. Read more in App