In an ecosystem, plants are autotrophs. The term autotroph means that plants are capable of changing sunlight into sugar. In other words, plants are
A)
consumers
B)
decomposers
predators
D)
producers

D)  producers

Explanation:

In an ecosystem, as plants are termed autotrophs, they are the producers.

An ecosystem is made up of both living and non-living components which co-exists together.

the answer is true when observing or determining population size, a direct observation is use, in which each organism is counted in a population or in an area. one benefit of this measure is that you get the exact population count but it will take a long time to  determine  the  size  of a  population.