某抗生素药物分子结构如下，拟进行该药物的人体药动学研究，为建立合适的血药浓度测定方法，根据分子结构，判定选用色谱条件。

根据分子特点，可以用于该药物测定的色谱系统是（）

A.多维高效液相色谱系统

B.气相色谱系统

C.气相色谱质谱联用系统

D.高效液相质谱联用系统

E.毛细管凝胶色谱

F.高效毛细管电泳色谱

Anyone who doubts that children are born with a healthy amount of ambition need spend only a few minutes with a baby eagerly learning to walk or a headp toddler starting to talk. No matter how many times the little ones stumble in their initial efforts, most keep on trying, determined to master their amazing new skill. It is only several years later, around the start of middle or junior high school, many psychologists and teachers agree, that a good number of kids seem to lose their natural drive to succeed and end up joining the ranks of underachievers. For the parents of such kids, whose own ambition is often inseparately tied to their children’s success, it can be a bewildering, painful experience. So it is no wonder some parents find themselves hoping that ambition can be taught like any other subject at school.
It’s not quite that simple. "Kids can be given the opportunities, but they can’t be forced," says Jaequelynne Eccles, a psychology professor at the University of Michigan who led a study examining what motivated first-and-seventh-graders in three school districts. Even so, a growing number of educators and psychologists do believe it is possible to unearth ambition in students who don’t seem to have much. They say that by instilling confidence, encouraging some risk taking, being accepting of failure and expanding the areas in which children may be successful, both parents and teachers can reignite that innate desire to achieve.
Dubbed Brainology, the unorthodox approach uses basic neuroscience to teach kids how the brain works and how it can continue to develop throughout life. The message is that everything is within the kids’ control, that their intelligence is

malleable

The word "bewildering" underlined in Paragraph 1 is closest in meaning to ______.

A．puzzling

B．unbelievable

C．unpleasant

D．awkward