Question

1. what is the main difference between noninfectious and infectious diseases?

infectious diseases are caused by pathogens; noninfectious diseases are not.
infectious diseases are spread from person to person; noninfectious diseases are not.
noninfectious diseases are more serious than infectious diseases.
noninfectious diseases are treatable; infectious diseases are not.

Explanation:

Infectious diseases are caused by pathogens (such as bacteria, viruses, fungi, or parasites). Non - infectious diseases are not caused by pathogens; they can be due to genetic factors (e.g., genetic disorders), lifestyle factors (e.g., heart disease due to poor diet and lack of exercise), or environmental factors (e.g., certain types of cancer from exposure to radiation).
The statement that infectious diseases are spread from person to person is not always true. Some infectious diseases can be spread from animals to humans (zoonotic diseases like rabies). Also, non - infectious diseases are not necessarily more serious than infectious diseases (e.g., COVID - 19, an infectious disease, has had a huge impact). And both infectious (e.g., many bacterial infections can be treated with antibiotics) and non - infectious diseases (e.g., some genetic disorders can be managed with certain therapies) can be treatable.

Answer:

Infectious diseases are caused by pathogens; noninfectious diseases are not.