Market Probe Study focused on investors’ knowledge of, attitudes toward and actual trading behavior related to options January 28, 2011. MILWAUKEE, WIS. –- In an effort to find out what US investors knew about ‘options,’ an under-utilized investment tool practiced by only a small percentage of US Consumer investors, TD Ameritrade, America’s #1 online broker, recently worked with Market Probe of Milwaukee to conduct a pivotal research study. “Market Probe’s Financial Services Practice....