单项选择题
For the following four molecules: acetone, benzene, dimethyl ether, ethane (each of which contains only one type of proton) the correct order of chemical shift (in δ units) is which of the following? ( )
A、Benzene < ethane < acetone < dimethyl ether
B、Benzene < acetone < dimethyl ether < ethane
C、Benzene > ethane > acetone > dimethyl ether
D、Benzene > dimethyl ether > acetone > ethane