Answer: three
Explanation:
A food chain is a distribution chain of matter and energy which occurs when one organism is consumed by the other organism. Trophic level can be define as the position an organism occupies in a food chain depending upon the feeding mechanism. For example, the plants or other autotrophs occupy the lowermost trophic level because they are capable of synthesizing their own food by the process of photosynthesis. They are called as producers. They are consumed by the herbivores they are called as the primary consumers. They are consumed by carnivores, they are called as secondary consumers. The secondary consumers are consumed by the big carnivores. They are called as the tertiary consumers.
The given food chain sunflower- beetle - mouse consists of three trophic levels. As the sunflower is the producer which is consumed by the beetle which is a primary consumer. Lastly the beetle is consumed by the mouse which is a secondary consumer.
