How should this sentence be changed?
Look at this fossil I bought it at the gift shop in the Museum of Natural History.
Question 7 options:

a)

Add a comma after bought

b)

No change needs to be made to this sentence

c)

Add a period after fossil

d)

Add a comma after fossil

C. Add a period after fossil

Explanation:

The reader can easily deduce that this is a run-on sentence.

"Look at this fossil," Is a full stop on itself, and the thought can end there.

The next phrase can be continued in a separate sentence by itself.

Many people seem to be confused as to why the answer isn't B, and I'll gladly explain why!

The sentence goes, "Look at this fossil I bought it at the gift shop.."

"It," causes the sentence to become a run-on, and therefore isn't grammatically correct.

However, if the sentence said, "Look at this fossil I bought at the gift shop," then it would have no need to be changed, as it is a full sentence in itself with no run-on.

Another thing to note is that some of you may be thinking, "But (insert grammar checker) said it was fine by itself!"

I'm sorry to break it to you, but a grammar checker doesn't have 100% guaranteed results. Many grammar checkers do not possess the ability to catch run-on sentences and are not a credible source of information.

I hope this clears things up!

your answer is c) experiments with water vapor showed that elements combine in specific proportions.