(C) It adds joy and wonder.
The rainbow is usually a symbol of joy and in this poem, God is said to have produced the rainbow with a simple smile. God then wraps the rainbow around his shoulder which relays an image of wonder.
When it is a linking verb, it contains a adjective right after the main verb (is/feel/were/was) and must express the person.
Example: I feel sad.
"Feel" is the main verb in this sentence and it is expressing ones emotion. So if that is the verb, then "sad" is the adjective. Because of this example, you can see that
"Were" in the sentence is the main verb and after those are the adjectives ( tired and dirty). Therefore, you just found a linking verb.
Then answer would be (A)
EMJOY!!
Yes, because they give off unhealthy fumes that go into our atmosphere and harm our environment.