Bacteria multiply by dividing into two cells. Under ideal conditions, with enough water and food and at a warm temperature, this can occur every 20 minutes. Usually, very small numbers of bacteria do not cause illness. A student removes her lunch from the fridge when it has 4 bacteria. Two hours later, while it is at room temperature, it has 256 bacteria. From the moment the food is taken out of the fridge, how long will it be before her food contains 16 384 bacteria?
- A2 hours
- B3 hours
- C4 hours
- D5 hours