Answer:
brainlest??
Explanation:
yes, bacteria can be both helpful and harmful to the human body, it can help digest food, breaks down carbohydrates and toxins, and help absorb the fatty acids that which cells need to grow.
Type 1 is correct! hope this helps!
~Zane
C. It makes your heart beat faster to supply more oxygen, which makes the heart stronger and enables it to pump blood more efficiently.