Should I pay the UCSA fee?

Hello there, I'm curious about the UCSA fee you mentioned. Could you please explain what it is for and why it's being charged? Is it a mandatory fee that everyone has to pay, or is it optional? Also, how does the money collected from this fee get used? I'm trying to make an informed decision about whether or not to pay it, so any additional information you can provide would be greatly appreciated. Thank you!