PLEASE HELP!
What is the difference between a food chain and a food web?

A. A food chain shows a direct relationship; a food web shows a complex relationship.
B. Food chains only occur in upper-latitude climates; food webs only occur in mid-latitude climates.
C. Food chains happen prior to photosynthesis; food webs occur post photosynthesis.
D. A food chain helps create a climax community; a food web sustains that community.