Which will give me the best audio?

(I’m using Windows 7 and Audacity 2.1.2)

I have a family history (spoken voices) audiotape from 1978. I had it transferred to a CD by a transfer company, and I had them save one disk as MP3 and another as .WAV because I have done a little work with Audacity and know a .WAV can still be edited.

However, I listened to all versions and the Original Audiotape is of better audio quality than either the MP3 or the WAV.
I don’t know enough to know if some quality is always lost in the transfer process.
So here’s my question:

A cousin I want to send a copy of the family history to says he is quite familiar with audio editing. (Not sure what program he uses.)
Should I send him the WAV file, or the original audiotape so he can make the best copies for other family members? Or does it make any difference?

Any advice appreciated. Thanks, Nancy

If the original tape is better, send it. But, it wouldn’t hurt to send a copy of the WAV too just in case the quality isn’t as good on his tape player.