B. I would assume. I say this because I don't think it would be spatial; chronological could be it, but that isn't always fun. Order of importance gets the story told. I could be C, but I think it's B.
I would say D. I know it looks weird, but that doesn't have anything to do with it. There needs to be a period after Friday because it is abbreviated, and there also needs to be a comma after Friday because a month comes next. There also needs to be a period after October because it is abbreviated. And then there is a period after 12 because it's the end of the sentence.
Plastic usage should be monitored because it can get into our water systems and pollute the oceans.
On the other hand, you may see the pearl as a symbol of something else with a different lesson to be learned. If that is so, write what you think that might be.
