KspAl(OH)3 = 1.3 × 10-33，如溶液中Al 3+ = 0.01 M，则沉淀Al3+的适宜pH为A:7.3-8.2 B:10-11 C:2.2-3.5 D:3.4-5.0 答案: 3.4-5.0