Answer:
The incorrect sentence is C. We should not buy grapes which scientists say are poisonous to dogs.
Explanation:
The commas should be placed like so,
We should not buy grapes which, scientists say, are poisonous to dogs.
I hope I helped!
Answer: To let the person reading that you are beginning the sentence
I believe the correct answer is D. is the author him?
Answer:
Teens who grow up moving to different areas all the time become more mature than others since their parents are not always around.
Explanation:
They are also more likely to enlist because children often take after their parents jobs.
Primary source, because he is the head of the country