Which of the Following Is an Explanation as to Why

Which of the following is an explanation as to why cyanobacteria blooms are prevented in oceans?

A) High availability of sulfate increases the rate of cyanobacteria growth, but abundance is grazed upon by zooplankton
B) Net primary productivity is low in all ocean zones and that prevents cyanobacteria blooms
C) A low availability of moldybenum in seawater slows the growth of cyanobacteria, which in turn grazing by zooplankton is sufficient to prevent blooms
D) All of the above