Pick from:
(I) calories;
(II) Light;
(III) atmosphere;
(IV) DNA;
(V) heat;
(VI) fossil fuels;
(VII) animals;
(VIII) photons;

Fact 1: Energy is passed up a food chain or web from lower to higher trophic levels. Fact 2: Calories are units of energy. Given the two facts above, what are passed up a food chain or web from lower to higher trophic levels?
Answer:
(I)