What is the best way to: To preheat the oven,

Available choices: a). press the bake button on the oven, set to the desired temperature, then wait until the oven beeps at you to know that it is at the desired temperature.. b). press the broil button on the oven, set to the desired temperature, then wait until the oven beeps at you to know that it is at the desired temperature..
Answer:
a).