题目

阅读理解 When I was a boy, myparents and I traveled from New York City to the Pennsylvania countryside for aweeklong taste of rural life. We stayed in a guesthouse on a farm, joining thedaily routines and eating meals with the farmer and his family. We got up earlyto see the cows as they were milked. I even tried my hand at milking one, andthen joined the farmer as he released the cows into the field afterward. Decades later I still havevivid memories of that trip which made me realize the value of a vacation, ofseeing new things, meeting new people and sharing memorable experiences withfa平面直角坐标系中，点A的坐标为（4，3），将线段OA绕原点O顺时针旋转90°得到OA′，则点A′的坐标是（ ）A．（-4，3）B．（-3，4）C．（3，-4）D．（4，-3）