Question

the system in the body that fights and protects against foreign invaders is ___.
the immune system
the cardiovascular system
the nervous system

Explanation:

The immune system's primary function is to defend the body against foreign invaders like bacteria, viruses, and other pathogens. The cardiovascular system is for circulating blood, and the nervous system is for transmitting signals. So the correct option is the one related to fighting foreign invaders.

Answer:

the immune system