Answer: Law of Demand
Step-by-step explanation:
The Law of Demand is based on what is demanded at the time. If something is demanded more than usual, then the price will be more than usual.
In February, there is Valentines Day, where the demand is higher because people want to buy chocolates for their loved ones. So, if Jack makes more chocolates to sell in February, he will make more than usual, because the price will have gone up and he will have more than usual to meet up to the demands standards.
Hope that helped a lot.
:)