如图，<img style='vertical-align:middle' src="https://www.bestkids.net/android-static/%E5%85%AC%E5%8A%A1%E5%91%98/d7905d0b89404a65bc2d2185902582df.001.png" width="59" height="19" alt="">与圆相切于点A和点B，C是圆上的一点，若<img style='vertical-align:middle' src="https://www.bestkids.net/android-static/%E5%85%AC%E5%8A%A1%E5%91%98/d7905d0b89404a65bc2d2185902582df.002.png" width="55" height="21" alt="">，则<img style='vertical-align:middle' src="https://www.bestkids.net/android-static/%E5%85%AC%E5%8A%A1%E5%91%98/d7905d0b89404a65bc2d2185902582df.003.png" width="57" height="19" alt="">（　）。<img style='vertical-align:middle' src="https://www.bestkids.net/android-static/%E5%85%AC%E5%8A%A1%E5%91%98/d7905d0b89404a65bc2d2185902582df.004.jpg" width="112" height="86" alt="">（）