Bitcoin fell below $90,000 on Monday as a sell-off gathered pace following the steepest monthly decline since mid-2021 and as renewed risk aversion drove investors out of stocks and digital assets. The world's largest cryptocurrency fell 6.1% at one point. By 1120 GMT, it was down 5.2% at $86,461, set for its biggest one-day fall in a month and hovering near last month's eight-month low of $80,