A, when the water is boiling, its temperature will no longer rise, so the option is incorrectly stated, which conforms to the meaning of the question;

B, the rice cooker has a metal shell, and a three-pin socket and a three-hole plug are used to prevent electric shock accidents caused by electric leakage in the pot. This approach is correct and irrelevant;

C, choose scissors with a longer handle than the knife edge to cut chicken bones, which is equivalent to increasing the power arm of the lever, so it can save labor, which is correct and irrelevant;

D, the total power in the circuit is too large, which is an important reason why the fuse is blown due to excessive current. It is correct and irrelevant to stagger the use of microwave ovens, rice cookers, water heaters, air conditioners and other high-power appliances to prevent overload.

So choose a.