WHAT IS KNOWN ABOUT THE INFLUENZA VIRUS

2. - 2 DE THI THU DH MON THI TIENG ANH VA DAP AN
Tiếng Anh 2 DE THI THU DH MON THI TIENG ANH VA DAP AN

2. What is known about the influenza virus?

A. It is first found in a group of very old birds. C. It existed over 100 million years ago.

B. All the different strains can be found in wild birds. D. It can survive in many different places.