Nearsightedness is the answer.
Answer: rising sea levels
Harsher/more frequent natural disasters
Answer:
The answer is Carbon Dioxide
This mechanism allows killer T-cells to hunt down and destroy cells that are infected with germs or that have become cancerous.
The other main type of T-cells are called helper T-cells.
Helper T-cells orchestrate an immune response and play important roles in all arms of immunity.
A hypothesis becomes a scientific theory when it has been thoroughly tested, and when whoever made the hypothesis now has proof of why their hypothesis was correct/incorrect.
