Removal of only one organism from a habitat can have a negative effect on other organisms. What details from the article support this claim? Think about what you know about organisms in their environment, and then explain how the details support the claim.

When we refer to microorganisms, if one is not there, the environment changes and another microbiota begins to predominate in the organism, which can be more or less pathogenic.

Explanation:

When the microorganisms that coexist and form the commensal biota, they live in an ideal equilibrium environment without generating pathology in humans, on the other hand, when this equilibrium is broken because some bacteria are absent, the pathology or infectious disease appears as it gives rise to to a rare biota such as pathogenic or transient.

i'm assuming that the correct answer is indeed the first one/ "a"..