下列各组物质互为同系物的是
| A.CH3CH2Cl与CH3CH2CH2Br |
| B.CH3CH2Cl与CH3CHCl2 |
| C.HOCH2- CH2OH与HOCH2 -CH2- CH2OH |
| D.CH2O和C2H4O2 |
| A.CH3CH2Cl与CH3CH2CH2Br |
| B.CH3CH2Cl与CH3CHCl2 |
| C.HOCH2- CH2OH与HOCH2 -CH2- CH2OH |
| D.CH2O和C2H4O2 |