In a food chain, green plants are described as

Explanation

1. 01

   Green plants make their own food from sunlight, water and carbon dioxide by photosynthesis, so they produce the energy that enters the chain.

2. 02

   That makes them producers, and they occupy the first trophic level.

3. 03

   Primary consumers are the herbivores that eat them, secondary consumers eat the herbivores, and decomposers break down dead matter at every level.