C. It makes a clear claim and relates to vaccinations.
I think talked is a different noun for spoke
Answer:
Yes, because it is the moral of a story or s message the author is trying to tell you. So it is important.
Their performance varies considerable, they are often idle, and then might have an occasional flurry of activity. For example, if their attendance is sporadic, they may have good attendance for a while, and then disappear unpredictably from time to time.