iPhone 14 Pro MPXV3YC/A, what country it is from?

The clue is the model number, A2890. If you refer to Identify your iPhone model - Apple Support you will see that is the generic model iPhone 14 Pro which is assigned for other countries which don't have a specific build. In other words, it is the "Rest of World" model so it could have been allocated to almost anywhere.

Model numbers: A2650 (United States, Puerto Rico), A2889 (Canada, Guam, Japan, Mexico, Saudi Arabia, and US Virgin Islands), A2892 (China mainland, Hong Kong, Macao), A2891 (Armenia, Belarus, Kazakhstan, Kyrgyzstan, Russia), A2890 (other countries and regions)

Every site that has that model for sale in it is Hungarian/Czechoslovakia.

Yes, same list here.

https://www.makeuseof.com/how-to-find-out-what-country-your-iphone-was-manufactured-in/

The reason for posting this link is they say to pay attention to the two letters before the slash to determine where the phone was intended to be used.

But, there is no YC entry. Only C and Y separately as Canada and Spain, which doesn't make sense.

The Czech Republic.

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