Which statement is true? a person's maturational, cultural, and historical experiences affect every genetic trait. genes have an effect on the final expression of all traits. genes determine whether a person becomes an alcoholic or develops type 2 diabetes. genetic expression of traits cannot be studied.

Genes have an effect on the final expression of all traits.

Explanation:

Genes are the stretch of DNA that code for a specific protein and thereby regulate genetic trait. Though environmental factors such as hygiene, nutrition, etc. also affect some of the traits of the organisms, genes are the major determinant of the expression of genetic traits.  

For example, irrespective of nutrition, physical activity, health, etc., the height of an individual depends on its genes for the height that it has obtained from its parents.  

answer: ice crystals in air

the water from the water body or another source of water gets evaporated as water vapor as an effect of heat on water. these water vapor rises in the upper layers of the earth atmosphere under high atmospheric pressure. the atmospheric pressure of these water molecules starts to decrease due to the effect of cold air. the invisible water vapor condenses into visible water droplets and ice crystals.these ice crystals and water droplets being less denser than the surrounding air floats on air as clouds.