题目

What is it that you love to do but never feel that you get it quite right? Perhaps you don't even try any more because you think what you do is not      enough． Discouragement seems to follow us a good part of the time,      however hard we work, it seems that there is      someone else who can do it much better． I have always enjoyed music and it is       to me that every musician has a      of their own．My father _        several instruments and when he played with other people, it was not difficult to      his sound in a group．Whether 在△ABC中，∠C=90°，D是边AB上一点（不与点A，B重合），过点D作直线与另一边相交，使所得的三角形与原三角形相似，这样的直线有（ ）A．1条B．2条C．3条D．4条