sand is uncountable and school is countable.
When you see a sentence not make sense it's usually because you are leaving out important words or mixing them up in the wrong way in that sentence so due to this knowledge a dangling modifier would be C.
D)
In, Twere profession of our joys/To tell the laity our love john Donne's " A Validation forbidding Mourning" speaker tell his wife that why should she keep his departure a secret.
Yes, because his mother taught him to look at the world not only from his own perspective, but also from other one. This will lead him to not judge a book by its cover and keep an open mind to others’ situations in the future.