题目

I will always remember my mother's last few days in this world.On February 14th,2000，my class went on a field trip to the beach.I had so much fun.When we returned to school，my teacher told me to go to the headmaster's office.When I got into the office，I saw a police officer.Suddenly I realized something was wrong.The police officer told me what had happened and we went to pick my sister up.After that，we went to the hospital and waited.Time went slowly.Finally，we got to see our mother.It was terrible.The next day，the headmaster came and told my two teachers what had happened.I was t某商店销售一种玩具，每件售价92元，可获利15%，求这种玩具的成本价．设这种玩具的成本价为x元，依题意列方程正确的是（ ）A．=15%B．=15%C．92-x=15%D．x=92×15%