From the date________on the coin, we knew that it was made 500 years ago. [ ]

A. marking    

B. marked

C. to be marked  

D. having marked

盐酸、稀硫酸等酸在水溶液里电离出的阳离子全部是______，氢氧化钠、氢氧化钙在水溶液里电离出的阴离子全部是______，所以酸、碱各具有通性．