Recent studies indicate that the addition of iron to areas of the ocean could increase productivity. Increased productivity could be beneficial for many reasons. What may be one of the largest negative impacts that could occur with ""fertilizing the oceans with iron""?

Explanation:

Fertilizers adds nutrients to the water. These nutrients if builds up in the aquatic system, it causes growth of the microorganisms which uses dissolved oxygen present in the water. One of the largest negative impact of adding iron to the oceans is that increased productivity will leads to increased respiration rates which leads to depleted oxygen in oceans. So, increased productive will affect the whole aquatic life.

i think its c. amphipod

the correct option is option d