At first I thought that the second option would give the most money after 31 days because it would eventually increase to over 10 pounds (so it would be higher that option 1 and option 3 seemed like the start point was so small that it would have increased by very little by the end of a month
I made an excel sheet for how much money I would receive every day in the month. I was surprised to see how much money I would make with option 3 so quickly. In a 31 day month I would earn 171,798,691.84 pounds. Compared to option 1 where I would earn 310 pounds and option 2 where I would earn 328.50 pounds this is a very very large amount.
Option 1 would be a better choice than option 2 on a February without a leap year. After that option 2 would become a lot better because every day you will be earning a lot more than 10 pounds a day.
If my family stopped giving me pocket money on the 8th day then I would be best of with option 1 where I would get 80 pounds. With option 2 and 3 I would get less money because the amount that I get, gets larger with every day and at the beginning it is not very much.
After day 11 option 3 has the most money. Using option 3 it would take you 28 days to become a millionaire!