Which sentence does not contain any errors in comma usage?

a.
it is, a hexagonal, traffic sign.

b.
jeremy has an old red wagon.

c.
the antique, and enormous clock stands in our living room.

d.
the stereo was designed with four, large speakers.

This question is obviously focused on commas, so if you say these sentences out loud and use breaks after every comma, you can tell which sentence doesn't make sense. So the answer is (d.).

the examples that saki used to represent satire through situational irony are options two (2) and five (5) inasmuch as the wolf thought that looking for a girl in the bushes could be as easy as hunting little pigs at the park, but it took him so much time to find the girl if it had not been not for a silly mistake. also, bertha would have survived to the wolf's hunt if she had not won those medals for goodness, which at the end they were what got her killed by making noise, so winning medals of goodness was not so good achievement, after all.