- A producer produces its own food
- Producer is a kind of role in the food chain process / in an ecosystem
- Hence, producer is a kind of role in the food chain system that produces food

- Producer is a kind of role in the food chain system that produces food
- The role of one type of plankton is to produce food
- Therefore, in the food chain process some types of plankton have the role of producer

- A producer produces its own food
- Producer is a kind of role in the food chain process / in an ecosystem
- So, producer is a kind of role in the food chain process that produces food

- Producing something is a kind of method for providing something
- Green plants provide food for themselves / animals / consumers by performing photosynthesis
- Hence, green plants produce food for themselves / animals / consumers

- Producer is a kind of role in the food chain process that produces food
- Green plants produce food for themselves / animals / consumers
- So, in the food chain process a green plant has the role of producer

- In the food chain process a green plant has the role of producer
- Seaweed is a kind of plant
- Hence, in the food chain process seaweed has the role of producer

- In the food chain process some types of plankton have the role of producer
- In the food chain process seaweed has the role of producer
- So, in the food chain process some plankton and seaweed both have the role of producer

- In the food chain process some plankton and seaweed both have the role of producer
- If two things both have a certain role then those two things have the same role
- So, in the food chain process some plankton and seaweed have the same role

So, in the food chain process some plankton and seaweed have the same role
Question: Plankton are tiny ocean organisms. The role of one type of plankton is to use the energy from the Sun to produce food that other animals eat. Which organism has the same role in the ocean as this type of plankton?
Context: - Producing something is a kind of method for providing something 
- Green plants provide food for themselves / animals / consumers by performing photosynthesis 
- Seaweed is a kind of plant 
- If two things both have a certain role then those two things have the same role 
- The role of one type of plankton is to produce food 
- A producer produces its own food 
- Producer is a kind of role in the food chain process / in an ecosystem