is 何に pronounced (1) なんに or (2) なにに here: お飲み物は何になさいますか。?

(1) [www.youtube.com/watch?v=fU-hnuSM098](http://www.youtube.com/watch?v=fU-
hnuSM098) @0:20 provides evidence (NB: despite the possibly incorrect ローマ字
(roumaji) found there and in the "show more" vocab list)
"お飲み物は何になさいますか。Onomimono wa nanni nasaimasuka?"

(2) but evidence from my Japanese keyboard's programming would suggest なにに is
correct because 何に doesn't pop up if I type なんに.

Finally, I thought even if it is なんに "nan ni", the mechanics of releasing the
ん to transition to the articulation of に necessarily produces a sound similar
to なにに

Please let me know, which is correct? (and if possible with a grammatical
explanation to understand why) thank you all for your kind assistance!
CC BY-SA 4.0
2021-01-31T05:39:11.800
83972
2023-06-21T19:08:41.130
2021-01-31T06:35:50.027
39793
39793
question
kanji pronunciation keigo
contradictory evidence for 何に as (1) なんに and (2) なにに
many sources indicate なにに is the preferred pronunciation of 何に in
formal/polite/keigo sentences/situations and is, therefore, the preferred
pronunciation in the example sentence due to its very formal/polite grammar:
お飲み物は何になさいますか?
CC BY-SA 4.0
2021-02-01T12:31:53.460
83992
2021-02-01T12:31:53.460
39793
83972
answer