Explanation:

Producer: A producer is an organism that can make its own food by using energy from the sun or chemicals in the environment.

Out of the given options, only grass is known as a producer because it can make its own food by using energy from the sun through the process of photosynthesis.

Let's understand the process of photosynthesis in detail:

Photosynthesis: It is a process in which green plants and some other organisms use sunlight to synthesize foods with the help of chlorophyll. In this process, plants absorb light energy from the sun and convert it into chemical energy, which is stored in the form of glucose.

Chlorophyll: It is a green pigment found in the leaves of plants that helps in capturing sunlight and converting it into energy.

Process of Photosynthesis: The process of photosynthesis can be divided into two stages:

1. Light-dependent Reactions: In this stage, chlorophyll in the plant's cells absorbs light energy from the sun and converts it into chemical energy in the form of ATP (adenosine triphosphate) and NADPH (nicotinamide adenine dinucleotide phosphate).

2. Light-independent Reactions: In this stage, the chemical energy generated in the previous stage is used to convert carbon dioxide and water into glucose and oxygen. This stage occurs in the chloroplasts of the plant cells.

Thus, grass is known as a producer because it can produce its own food through the process of photosynthesis using energy from the sun.

Because they make their own food . like - Grass , plants ,tree and the correct answer is B