The statement that best compares the effects of absolute monarchy and constitutional monarchy is:
"An absolute monarchy is overly dependent on a single monarch, which can lead to a system that is overthrown, while a constitutional monarchy can bring long-term stability."
This statement highlights the potential risks associated with absolute monarchy, where the concentration of power in one individual can lead to instability and the risk of overthrow, whereas a constitutional monarchy, which operates within a framework of laws and limitations on the monarch's power, can promote stability and governance through shared authority.