Answer:
A, and B.
Explanation:
A and B are the ones that are physical. The others are social and economic.
The development of agriculture was set in motion by hitching animals to the plow. The correct option among all the options that are given in the question is the second option. At the beginning, people did not use animals for agricultural purpose, but with passing of time the utility of the animals for agriculture was understood and it made cultivation easy.
Answer:
Correct answer is (a). Assimilation of immigrants into the existing population.
Explanation:
The frequency distribution will not change from generation to generation once a population is in Hardy-Weinberg equilibrium. However, on assimilation of immigrants into the existing population, the equilibrium will definitely change.
