题目

Born on August 9,1963,New Jersey,Whitney Houston almost seemed bound to become a singer.Her mother Cissy Houston was the choir（唱诗班）minister at New Hope Baptist Church,and it was there that a young Whitney got her start. When she was 19,Whitney Houston was discovered in a nightclub by the famous Clive Davis of Arista Records. In 1983,Houston made her debut（首演）on national television.In 1985,she released her debut album Whitney Houston and almost immediately became a sensation.Over the next year,her hit singles Saving All My Love for You and How Will I Know helped the al如图所示的轻质杠杆OA上悬挂着一重物G，O为支点，在A端用力使杠杆平衡．下列叙述正确的是（ ）A．此杠杆一定是省力杠杆B．沿竖直向上方向用力最小C．此杠杆可能是省力杠杆，也可能是费力杠杆D．沿杆OA方向用力也可以使杠杆平衡