The removal of a keystone species from a community usually results in: a. the death of all other community members. b. the disappearance of that community. c. substantial changes in the abundance of many species. d. minor changes, if any.

Option B (disappearance of that community)

Explanation:

Keynotes species are species of organisms that greatly affect the structure of its environment.

Keynotes species plays great role in ensuring the structure, checkmating the abundance and diversity of other species of an ecosystem.

In absence of keystone species, the ecosystem will be overpopulated above the carrying capacity (i.e the resources available for organisms in their ecosystem) will definitely leads to competition, disease outbreak, malnutrition etc.)

However, when the important primary producers of the ecosystem (Plants species) are wiped out due to overfeeding caused by abundance of herbivores that supposed to be checkmated by the keystone species. Hence, the extinction of plants will cause the extinction of other organisms in that community. Thus, the community will cease to exist.