As sea levels rise, which of the following will affect marine biodiversity? The acidity of the oceans will decrease. Underwater plants will receive less light. Oxygen levels throughout the sea will increase. The frequency of tsunamis will increase.

Because the factor of sea level rise (SLR) is included, before answering the main question (what can affect marine biodiversity), we first need to answer which among the choices will be brought about by SLR when acting alone. Only the choice 'underwater plants will receive less light' can be directly brought about by SLR. Therefore, we can also say that among the choices, it is the only one that can affect marine biodiversity. In what way? Aside from plankton, underwater plants also serve as food for marine animals. Higher sea levels may result to a larger distance between the surface and the sea floor, reducing the amount of available light. Reduced light availability may compromise the growth, and ultimately the life and presence of underwater plants. This will affect all the other organisms that depend on them.