It's been a stellar year for voice artificial intelligence (AI) company SoundHound AI (SOUN -4.75%), which, as of last week, has soared more than 600% since January. The stock has become one of the more prominent AI stocks to own of late, with its market cap now at more than $5 billion.The stock rose to popularity this year after investors learned that Nvidia had invested in the business. However, whether or not it can continue rallying next year will likely depend on answers to three crucial questions.1. C ...