下列分子中不含手性碳的是( )
A:CH3CHBrCH(OH)CH2CH3
B:HCOOCH2CH(CH3)CH2OOCH
C:CH3CH(OH)CHO
D:CH2(OH)(CHOH)4CHO
With great efforts____ (focus) on the conservation project, the number some rare animals is steadily increasing.
保护动物多样性的最有效的措施是( )
如图所示实验能够说明( )