Read the passage.
Which sentence best summarizes the article?
A
Over the last twenty years, Type 2 diabetes has increased in the United States due to the growing number of overweight adults.
B
Scientists felt that, since exendin causes Gila monsters to make more insulin, it might have a similar effect in humans.
C
The chemical exendin, found in lizard saliva, is known to increase the production of insulin in Gila monsters.
D
A new drug, based on Gila-monster saliva, shows promise as a way to regulate insulin in people with Type 2 diabetes.