No improvement to this sentence is necessary. It makes perfect sense on its own and sounds right. "Either" always takes an "or" else the word wouldn't make sense, as it's meant to contrast binary options.
eg.
I'm either going to eat food or drink water.
Pretty sure the answer is A
It’s probably best to be straight up and ask. But if you don’t want to do that, you could just mention her up in passing. Such as “Hey did you see what Anna posted?” (let’s say Anna) or maybe some thing like “hey I literally thought I saw Anna at Walmart” and then when this person is somehow brought up, you could be like “speaking of which, I didn’t see her at the party? Everything okay?”
The answer is C.) Age does not equal wisdom.