Since A, B and C are correct. I think the answer is D. Linguistic grammaticality and content or effective communication are separate matters.
You can try and use a website called "essaytyper"
https://www.google.co.il/url?sa=t&source=web&rct=j&url=http://www.essaytyper.com/&ved=0ahUKEwjo2ejWkMjMAhWEthoKHbZVCXUQFggZMAA&usg=AFQjCNFwouC2BTYfkMolos7xZtypikaUfg&sig2=agdG-xRxRrum1I49HNKV6w
Thnx I need to get more lol
Answer:
it's a tough decision but the answer is A)
