听力原文：M: The Republican Party in America is opposing stem cell research. I find it hard

to believe that in this day and age,someone would do that.

W: Stem cell research sounds pretty impressive,I'll admit.But just what is it？

M: Well,a stem cell is a special type of cell.It is a general cell that.when it divides.Call become any specific type of cell.

W: You mean,a stem cell can become a heart cell？Or a brain cell or a kidney cell？

M: That's about it.Stem cells are a part of the body's maintenance and repair system.When they divide, they can become any cell type.

W: I guess there would be some tremendous medical advantages in that sort of research.

M: You've said a mouthful.Recently,scientists were able to help a man who lost a jawbone from cancer.They recreated bone material for his jaw from stem cells.What it means is that since the new bone was created out of the person's own cells,there was no problem with rejection because the DNA was the same.

W: I bet the person was delighted.Why would anyone oppose that sort of research？It would seem to have endless potential to benefit the human race.

M: I agree,but there are people who think we should not interfere with nature and mainipulate"what is not natural".

W: It is easier to hold such a narrow view if you're not in a position to need the benefits of the research.If you're missing a jawbone because of cancer,you probably support the research.

What is the man's attitude toward the stem cell research？

A．Supportive.

B．Opposed.

C．Pessimistic.

D．Neutral.