12 points
Which sentence correctly uses punctuation to separate items in a series?
We saw retrievers, terriers and shepherds, competing at the dog show.
He needed to pack lightly and only brought two, shirts two, pairs of pants and a sweater.
Don't forget to bring your pencils, paints, and an easel to the art class.
Cirrus, cumulus, and stratus, are the three main types of clouds.