In an ecosystem, what do organisms and populations with similar needs compete
over?

In any ecosystem, organisms and populations with similar requirements for food, water, oxygen, or other resources may compete with each other for limited resources, access to which consequently constrains their growth and reproduction. Growth of organisms and population increases are limited by access to resources.

b. Clear cutting

Explanation:

Clear cutting is the correct option. Clear cutting involves the clearing up of entire vegetation cover of the region or cutting up of trees. This will lead to loss of canopy cover from a region. This will cause loss of biodiversity of a region as the animals, birds and insects will loose their habitat. Such faunal species may translocate to new region, decrease in number or may extinct.