Which of the following is a community? A. All of the nonliving things that make the lake inhabitable O
B. All of the fish, bacteria, and mammals that live in a lake
C. All of the living and nonliving things that interact in and around a lake
D. All of the trout that live in a lake

B. All of the fish, bacteria, and mammals that live in a lake

Explanation:

In terms of biology an individual make population, population makes a species and interaction between different species makes community. Interaction of living and non-living things make an ecosystem.

Community involves interaction between all the living organisms present in a given environment. Hence, interaction between fish, bacteria, and mammals that live in a lake is a community.

Hence, the correct answer is "B. All of the fish, bacteria, and mammals that live in a lake".

genetic variation can be caused by mutation (which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism's offspring).