题目

This is a highly _____________ (有争议的) subject, but he is not going to avoid it in his writing. 答案：controversial  某些玻璃仪器，为保证其密闭性，常常把玻璃的接触面处磨毛（也称磨砂），下列仪器的口部经过了磨毛处理的是（ ）A．量筒B．集气瓶C．烧杯D．试管