From the list which type of system, so with the best option for healing the widest variety of diseases?

Embryonic stem cells
Bone marrow stem cells
Skin stem cells
Small intestine stem cells

From the list provided, embryonic stem cells have the potential to develop into any type of cell in the body, making them the best option for healing the widest variety of diseases. They have the ability to differentiate into all three germ layers, giving them the potential to treat a wide range of conditions and diseases. However, it is important to note that the use of embryonic stem cells is limited due to ethical concerns and regulatory restrictions.