American money & credit cards in Banff & Jasper National Parks (Canada)?

Hi – I’ll be driving to Banff and Jasper National Parks in Alberta, Canada in a few days. I’ve already made reservations for campsites, but will need to pay for gas, park admission, and miscellaneous food and expenses while in the parks. To pay for things like this (particularly in Banff, Lake Louise, Jasper, and then throughout southern Canada on the drive back home to Wisconsin), will I:

A) Be able to use my Visa debit card like I can at home in the US,
B) Need to bring along a lot of cash and convert to Canadian dollars, or
C) Just be able to bring along American dollars and spend it like in the US?

Thanks for any help – I haven’t traveled in Canada much at all!!