Answer:
Definitely A is the correct option
A compass
The Earth's magnetic field, provided by the magnet in a compass, shows the direction of the north and south poles.
ANSWER MADE BY AN AI
C. calcium is your answer
<span>Some 120 prescription drugs sold worldwide today are derived directly from rainforest plants. And according to the U.S. National Cancer Institute, more than two-thirds of all medicines found to have cancer-fighting properties come from rainforest plants. Examples abound. Ingredients obtained and synthesized from a now-extinct periwinkle plant found only in Madagascar (until deforestation wiped it out) have increased the chances of survival for children with leukemia from 20 percent to 80 percent.</span>