题目

—Mike, your car looks very old. Why not buy a new one? —_________ my car is very old, it still runs very well. A. Although         B. When       C. Because          D. If 答案：A如图，AB和CD都是⊙O的直径，∠AOC=50°，则∠C的度数是（ ）A．20°B．25°C．30°D．50°