His teacher told him that since his parents were working abroad , either his grandparents or one of his uncles ______ allowed to come to the parents’ meeting .

A．was

B．were

C．are

D．is

农村公路防护工程的圬工砌体要求( )。

A．必须选用无风化、无水锈石料，强度及尺寸应满足设计要求

B．砂浆拌制必须采用重量法计量，机械拌和

C．石料砌筑前应洒水冲洗干净，大面朝上

D．已完成砌体不得扰动，注意养护

E．临空面砌体应勾凹缝，勾缝应均匀美观