Which describes a group of organisms that are members of a species?

They can breed and produce offspring that can breed.

Explanation:

The options you were given are the following:

A species can be defined as a group of similar organisms that can reproduce and produce offspring that can produce as well. This is why the first option is the correct one.

In ecology, the term community refers to a group of populations of two or more different species that inhabit the same area. More than one species can be found in a biome and ecosystem as well, which is why the second and third options are incorrect.

Some organisms can look very similar but belong to different species. This is why the fourth option is not correct, either.

a catalyst

Explanation:

Catalyst is a substance that influences the rate of reaction without being consumed in the reaction. They increase the rate of reaction by decreasing the activation energy of the reaction. In biological system, enzymes are referred to as biological catalyst or biocatalyst. They are generally protein in nature and are very specific for their substrate. They also increases the rate of biological reaction by forming enzyme-substrate complex.

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