Which sentences are punctuated correctly? check all that apply.
a. the circus featured four clowns, three acrobats, and a tightrope walker.
b. we will bring a flashlight, sleeping bags and a tent on the camping trip.
c. the recipe calls for two eggs; a cup of flour; salt and baking soda.
d. i wrote poems about my best friends, the queen of england and the tooth fairy.
e. the flags are blue and white; red, white, and blue; and red, white, and green.
more then one ! : )

The answer to your question would be that the sentences that are punctuated correctly are the following ones: The circus featured four clowns, three acrobatas, and a tightrope walker and the flags are blue and white; red, white and blue; and red, white, and green. That is, your answers woud be A and E.

The comma used in these sentences is known as the Oxford comma. This comma is the final comma in a list of things. The use of the Oxford comma is up to you. Still, omitting it can cause misunderstandings, such as in D.

d) I wrote poems about my best friends, the queen of England and the tooth fairy

D is understood as if the speaker's best friends were the queen and the tooth fairy.