Which scenario describes the removal of strong top-down control that triggers a cascade?

Answer

The absence of a keystone predator causes the structure to shift upward in population size.

The key mechanism is the release of strong control at the upper end of the food web, resulting in an increase in herbivores and a subsequent decline in producer health.

Which scenario describes the removal of strong top-down control that triggers a cascade?
EcologyEcosystemPredatortrophic cascadefood web