—Kate, what is _______ hobby class at your school? 

—Maybe the piano lessons. Seven out of ten girls in my class take the lessons at the weekend.[ ]

A. more popular

B. the most popular

C. as popular as

D. less popular

石油沥青的黏滞性一般采用针入度来表示。针入度是在温度为25℃时，以负重100g的标准针，经5s沉入沥青试样中的深度，每深1／10mm，定为1度。针入度数值越小，表明黏度越大。