We can rule out small fish and grasses. My guess is that zooplankton get their energy from phytoplankton, because phytoplankton use photosynthesis to get their energy.
Answer:
DNA sequencing is the process of determining the nucleic acid sequence – the order of nucleotides in DNA. It includes any method or technology that is used to determine the order of the four bases: adenine, guanine, cytosine, and thymine.