I'm not sure if you have choices or not but many abusers use substances to numb feelings in order to avoid negative feelings.
Numb
The second line of defence is a group of cells, tissues and organs that work together to protect the body. This is the immune system.
When a pathogen (disease-causing organism) invades the body, the neutrophils gather at the entry site and try to engulf it and destroy it.
A T helper cell will recognise only one pathogen. If the T helper cell recognises the invader, it will immediately clone to increase numbers.
After a few days of fighting off the pathogen, you will recover from your infection.
The answer is letter
D.
<span>
Communicable diseases
are also known as infectious or contagious diseases. They may come from food,
water, animals, another person, or anything that comes from the environment. <span>Airborne
viruses, bacteria, blood, and bodily fluids can cause the spread of these
diseases. The most common communicable disease is the flu, which can easily
spread in an enclosed environment with a recycled circulating air (e.g.
air-conditioning). Infectious disease caused by blood contact like HIV/AIDs are
also dominant in society. </span></span>