The amount of milk purchased at grocery stores in East African countries varies dramatically based on the local population's lactose tolerance phenotype. Based on what we've previously discussed in class, this trend is explained best by what component of phenotype variance?

Environmental variance

Explanation:

The portion or part of the phenotype variance which is due to  the differences in the environments in which the individuals in a population has been exposed.

These type variation is caused by factors Which are found in the environment.

examples of such factors are

1. diet

2. Temprature e.t.c

just like the example cited in the case in East Africa milk purchased is less due to their lactose tolerance this is an example of an environmental variance.

answer: national resource conservation services

national resource conservation services is the us. based approach that provides technical and financial assistance for natural resource management. nrcs society in conservation of resources by involving in activities like farmland protection, flood prevention, watershed protection, urban conservation, conserves economic and environmental conditions. it conducts soil surveys and implements the policy of natural resources management on the society.

the rocks are classified by the geological process they are formed by. the three main groups of rocks are igneous, metamorphic, and sedimentary. minerals are not they are classified under the chemical classes they are in. these groups include silicates, sulfates and carbonates.