Answer:
Excessive nutrients from fertilizer run off.
Explanation:
Scientists have suspected that phytoplankton blooms might be connected to agricultural run-off. They got some evidence from a recent study by comparing the timing of irrigation along the west coast of Mexico and phytoplankton blooms in Mexico’s Sea of Cortez. During the comparison, they had found a close correlation. Phytoplankton blooms occurred in the Sea of Cortez shortly after the irrigation. This happened because of carried fertilizers after irrigation and other agricultural run-offs into the sea.
The bloom detected in the Gulf of Mexico on December 13 might be similarly linked to agricultural run-off.
The dominant ones. Whatever has been gained through evolution in adaptation to their specific environment.
Scientists and biologists study the world using experimentation. This can be done through observation, or by performing scientific tests in a lab.
I think it’s the first one - a , but I could be wrong