Answer:
A) I mean, come on, these parents need to wise up and not be so stupid about the measles! Is the correct answer.
Explanation:
The tone in the first option would be the proper one if the conversation were taking place among friends because it uses informal expressions and words that shouldn't be used when discussing a topic such as disease. So, if the passage is formal, the others fit so A is correct.
Hypothesis, a prediction based on what you know.
B will me the right answer