Alien means something is completely foreign to you. You don't necessarily know anything about it while familiar means it's something you know well. I am familiar with the Hunger Games series because I've read it. However, I have never read Don't Cry so its alien to me. They are complete opposite words, they're antonyms.
I’m not 100% sure what you’re trying to say here, but I believe the answer is d.
The answer is A, The greenhouse effect is changing Earth's atmosphere.
Answer:
bet
Explanation:
let me see that stuff happen