Which sentence correctly joins these three simple sentences to create one compound sentence?

I pitched our tents. Robyn started a fire. Franco refilled our canteens.

a. I pitched our tents, Robyn started the fire, Franco refilled our canteens.
b. I pitched our tents, Robyn started a fire, and Franco refilled our canteens.
c. I pitched our tents and Robyn started a fire and Franco refilled our cantee