MicroStrategy (MSTR -10.59%) stock saw big sell-offs in Tuesday's trading. As of 3:15 p.m. ET, the company's share price was down 11% amid a 1.1% pullback for the S&P 500 index and a 1.9% decline for the Nasdaq Composite index. Meanwhile, the price of Bitcoin (BTC -5.74%) was down 5% over the past 24 hours.With its heavy investments in the market-leading cryptocurrency, MicroStrategy has effectively turned itself into a bet on Bitcoin. With the token losing ground today and the broader stock market facing s ...