How does the size of phytoplankton determine how much carbon is sequestered in the oceans?

a) Smaller phytoplankton are more toxic.
b) Smaller phytoplankton are more likely to be eaten by large zooplankton.
c) Larger phytoplankton photosynthesize more rapidly.
d) Larger phytoplankton are more likely to sink to deeper depths in the ocean.