Answer:
Today, drug-resistant infections are a serious threat to people's health. Hundreds of thousands of lives are lost every year because of infections that can no longer be treated with existing drugs. Discovering new antibiotics, able to kill drug-resistant bacteria, is essential to saving modern medicine.
The heart is an example of an organ.
Answer: Option A) Oxygen may not have been able to accumulate in the atmosphere
Explanation:
Ozone, O3, is an allotrope of oxygen having three atoms in the molecule instead of the usual two present in molecular oxygen. Ozone is generated from oxygen, and is the only form in which oxygen can exist in the atmosphere.