What is the function of the insulin hormone?

The correct answer is Option (2) → Regulates blood sugar level

Insulin is secreted by the beta cells of the islets of Langerhans in the pancreas. It helps the cells take up glucose from the blood and store the surplus as glycogen, thus keeping the blood sugar level within limits.

When too little insulin is produced the blood sugar rises and the condition is called diabetes mellitus. Growth is the work of the growth hormone and metabolism that of thyroxine.