The doctor ______ Mrs. Black carefully and told her nothing was wrong with her. [ ]

A. looked up

B. looked over

C. looked for

D. looked like

(3分)学以致用。在①NaOH, ②Ca(OH)₂，③Al(OH)₃等三种物质中：

(1)能用于治疗胃酸过多的是___________(填番号，下同)；

(2)能用于制造肥皂的是__________；

(3)能用于改良酸性土壤的是___________。