A、Helpful. B、Secure. C、Useless. D、Promising. C

W: John, have you chosen a physical education class yet for this semester?
M: No. Why?
W:(12)You gotta take rock-climbing. We just had the first class and it looks like it is going to be great.
M: You think I should take rock-climbing? You’ve got to be kidding. Besides, how can they teach rock-climbing when it’s completely flat around here?
W: That’s not important. You can’t just start climbing without any training. You had to get in shape, learn how to use the ropes, the belts, the buckles, there’s a lot of preparation first.
M: You don’t think it’s just a little bit dangerous?
W:(13)Not if you know how to use the safety equipment, which is, by the way, pretty hi-tech. The ropes are made of flexible fabrics that stretch a little, the shoes have special grips on the bottom, and the helmets made some kind of special plastic. You have to learn how to use all these before you do any real climbing.
M: Well, what’s the appeal?(14)We’ll spend the whole semester studying something we don’t actually get to do.
W: We will take a climbing trip during spring break. But that’s not the point.(15)Climbing isn’t the only goal. In preparing to climb you learn patience, mental discipline, and you gain fantastic physical strength, especially in your hands. For the first few weeks we’re gonna concentrate entirely on hand and upper body exercises.
M: All that in one sport? Maybe you are right. Since it’s not too late to join the class, maybe I will.