Answer:
B. KN
C. PP Online
Explanation:
KN is A's own software for creating slideshow presentations. However, since most people using KN are coming from using MS PP, there is the option to open PPs in KN (albeit with some fonts missing).
You can also view the file from PP Online. Just create a MS account (if you don't already have one), download the email attachment and upload it to your cloud, and you should be able to view it there.
