* Καθαρίνα (Katharina): This is a very common and direct transliteration of Katherine/Kathryn. It's probably the closest and most easily understood option.
* Αικατερίνη (Aikaterini): This is another very common Greek form of the name Catherine, and it's also widely accepted. It's perhaps a slightly more traditional or formal sounding option.
* Καθηρίνη (Katherini): This is a less common but still perfectly acceptable variation.
The best choice depends on personal preference and context. Καθαρίνα (Katharina) or Αικατερίνη (Aikaterini) are your safest bets for clarity and widespread understanding.