Which sentence shows correct comma usage?
Hector was tired and hungry, so he plopped down on the couch and
devoured the pepperoni pizza.
Hector was tired, and hungry, so he plopped down on the couch and
devoured the pepperoni pizza.
Hector was tired and hungry, so he plopped down on the couch, and
devoured the pepperoni pizza.
Hector, was tired and hungry so he plopped down on the couch, and
devoured the pepperoni pizza.