Answer:
B. Sternum
Explanation:
The sternum (or breastbone) is a flat bone in the thorax's anterior area. It has a 'T' shape and is located in the center of the chest. The sternum, which is part of the bony thoracic wall, protects the internal thoracic viscera, such as the heart, lungs, and oesophagus.
Here is a picture from the internet.
The correct answer is “B”
I hope this helps
I think it’s proteins and nucleic acids
The immune system<span> is made up of a network of cells, tissues, and organs that work together to protect the body. One of the important cells involved are white blood cells, also called leukocytes, which come in two basic types that combine to seek out and destroy disease-causing organisms or substances.</span>
