House sparrows in the northern part of North America are larger than those found in the southern regions. The possible mechanism of microevolution is more likely to be responsible for this is natural selection. The answer would be letter B.
Technically there is no direct connection between air pressure and humidity. Humidity is the amount of water vapor in the air or air parcel. Air pressure is its weight of the air in a column, the true connection is in the temperature.
Due to photosynthesis, plants convert Sunlight and Carbon Dioxide into Oxygen. All living things breathe in this gas (Oxygen).
