Question

what is one of the main functions of the gallbladder?
store and concentrate bile
secrete bile directly into the small intestine
produce insulin for digestion
store and concentrate stomach acid
filter waste products from the blood

Explanation:

The gallbladder stores bile produced by the liver and concentrates it by absorbing water. Bile is secreted into the small intestine when needed for digestion. Insulin is produced by the pancreas. Stomach acid is in the stomach. Filtering blood waste is a liver or kidney function.

Answer:

Store and concentrate bile