The organisms built up a resistance to the mercury. The mercury passed through the food chain. The plankton made the mercury safe. The fish would not eat the plankton.
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: A factory in Japan had been dumping mercury into Minamata Bay. Certain microorganisms in the water were able to change the mercury into a form that the plankton could use. Which most likely happened next?
Possibilities:
- The organisms built up a resistance to the mercury.
- The mercury passed through the food chain.
- The plankton made the mercury safe.
- The fish would not eat the plankton.

The mercury passed through the food chain.