Q: Fact 1: Energy enters ecosystems in the form of sunlight or chemical compounds. Fact 2: Oceans are one of the largest ecosystems in the world. Given the two facts above, what can enter oceans in the form of sunlight of chemical compounds?

pick from the following.
(1). NaCl
(2). heat
(3). copper
(4). Energy.
(5). energy
(6). coal
(7). Fungi
(8). photons
A:
(5).