Which two hormones are key in regulating blood sugar levels?

Insulin and glucagon play critical roles in the regulation of blood sugar levels. Insulin, produced by the pancreas in response to elevated blood glucose levels, facilitates the uptake of glucose into cells, particularly in muscle and fat tissues, thus lowering blood sugar levels. It also promotes the storage of glucose as glycogen in the liver and muscle tissues.

Glucagon, on the other hand, is released when blood sugar levels drop. It stimulates the liver to convert glycogen back into glucose, which is then released into the bloodstream. This process helps to raise blood sugar levels when they fall too low, providing a counterbalance to the effects of insulin.

Together, these two hormones maintain homeostasis in blood sugar levels, ensuring that the body has a stable source of energy at all times. The other options do not have the same direct regulatory effect on blood glucose.