When a frog eats grasshopper which thrives on the green plant, the frog is
A. Primary producer
B. Herbivore
C. Primary carnivore
D. Top consumer

Hint: A food chain explains which organisms in the environment eat which other organisms. A food chain is a series of organisms in which nutrients and energy are transferred from one to the next. When one organism consumes another, this occurs.

Complete answer:
A food chain is the sequence of events in an ecosystem in which one living organism eats another organism, which is then eaten by a larger organism. A food chain is the flow of nutrients and energy from one organism to another at different trophic levels.
The feeding pattern or relationship between living organisms is also explained by the food chain. A trophic level refers to the order in which producers, primary, secondary, and tertiary consumers appear in a food chain, starting at the bottom with producers and ending with primary, secondary, and tertiary consumers. A trophic level is the lowest level in a food chain.
All organisms that rely on plants or other organisms for food are considered consumers. Because it contains almost all living organisms, this is the largest part of a food web. It includes herbivores (animals that eat plants), carnivores (animals that eat other animals), parasites (organisms that live on and harm other organisms), and scavengers (animals that eat dead things).
The primary consumers are those who consume the products directly from the producers (plants). Herbivores, in other words, are the primary consumers. Secondary consumers are carnivores that eat plant-eating animals (herbivores). A primary consumer is a grasshopper that feeds on plants, while a secondary consumer or primary carnivore is a frog that eats the grasshopper.

Thus, the answer is option C: Primary carnivore.

Note: Herbivores have rows of wide, flat teeth that are used to rasp, grind, and tear tough plant material and woody stems; primary consumers often have specific physiological adaptations that allow them to process the carbohydrates produced through photosynthesis, which can be difficult to break down and extract nutrition from; and primary consumers often have specific physiological adaptations that allow them to process the carbohydrates produced through photosynthesis, which can be difficult to break down and extract nutrition from.