What attaches itself to this jet stream and it sense tells you where the stratosphere begins

well, that's easy; the answer's c, "it reduces contamination of the water and substrate of the estuary."

you can't see the options

desert perennials often survive by remaining dormant during dry periods of the year, then springing to life when water becomes available. most annual desert plants germinate only after heavy seasonal rain, then complete their reproductive cycle very quickly.