Ontario Grade 9 Science Class Practice Exam

A food web consists of multiple interconnected food chains that show the flow of energy among organisms in an ecosystem. While option A correctly describes the steps of energy transfer, it does not include connections between different food chains. Option C is a partial definition of a food web, but does not fully encompass the system. Lastly, option D refers to a different concept, the study of interactions in an ecosystem, and is not an accurate definition of a food web. Therefore, option B is the most complete and accurate description of a food web.