People with diabetes often receive insulin injections. What effect does insulin have on the body?

A. It raises blood-sugar levels.

B. It lowers blood-sugar levels.

C. It raises glucagon levels.

D. It lowers glucagon levels.

Insulin injection is used to control blood sugar in people who have type 1 diabetes (condition in which the body does not make insulin and therefore cannot control the amount of sugar in the blood) or in people who have type 2 diabetes (condition in which the blood sugar is too high because the body does not produce