Why msfconsole is always showing "please answer yes or no"

As you can see, i installed metasploit and cd to /opt/metasploit-framework/bin, then type ./msfconsole. According to the prompt shows, i tried to type yes, but it failed... It is still showing the prompt answer yes or no...and won't stop until I type ctrl+C to block it. What shall i do to make it right? (The OS is Mac-OSX)