The answer is C for both because they follow the correct syntax and conventions of english to allow the reader to effectively read the sentence without confusion.
You're right, the answer is caring. :)
Answer:
Scientists are creating vaccinations that prevent people from getting the bird flu. If the virus mutates, a new vaccine will need to be made. The vaccine needs to be tested, which can be dangerous. It will also take a long time for scientists to know whether the vaccine works or not.
Explanation:
The flu vaccine is injected under skin in a inactive form and the immune system responds with antibodies to the food protecting you from the future exposure to the flu. That's why sometimes you get the flu even though you got a shot because there's different forms of the flu.
