单项选择题
A.0.77% B.2.1% C.4.3% D.6.69%
A.0.0008% B.0.0218% C.0.77% D.2.11%
A.0.77%~2.11% B.0.0008%~0.0218% C.0.0218%~0.77% D.0~0.0218%