Which factor can cause secondary succession?

Disturbances like flood, fire and human activities.

Explanation:

Secondary succession is a type of ecological succession that occurs mainly on the preexisting soil. Secondary succession mainly occurs due to the natural and human disturbances in an already established ecosystem.

Flood can flow all the natural vegetation of the ecosystem and results in the death of living organisms of that ecosystem. Fire can burn the whole ecosystem and reduces the natural vegetation of that ecosystem. Human activities like deforestation can reduce the number of plants and animals of that ecosystem. Secondary succession reestablishes life in the previously destroyed ecosystem. This succession is much faster than primary succession.

the correct answer is option b

behavioral response need communication and thus co-ordination at several levels such as interaction among cells, organ system and the entire organism.

behavioral response produces both internal and environmental stimulus.