[求助]有几题不懂，想请教下大家

蓝宝书68题

Teresa:manned spaceflight does not have a future, since it cannot compete economically with other means of accomplishing the objectives of spaceflight.

Edward:no mode of human transportation has a better record of reliability: two accidents in twenty-five years. thus manned spaceflight definitely has a positive future.

which of the following is the best logical evaluation of Edward's argument as a response to Teresa's argument?

A. it cites evidence that ,if ture , tends to disprove the evidence cited by Teresa in drawing her conclusion.

B. it indicates a logical gap in the support that Teresa offers for her conclusion.

C. it raises a consideration that outweighs the argument Teresa makes.

D. it does not meet Teresa's point because it assumes that there is on serious impediment to transporting people into space,but this was the issue raised by Teresa.

E. it fails to respond to Teresa's argument because it does not address the fundamental issue of whether space activities should have priority o er ther claims on the national budget.

答案是D

Teresa expressed  " manned spaceflight cannot compete with other means"  by showing ecnomical disadvantages manned spaceflight has

so if Edward wants to disfute her opinion effectively ,he shall also show sth related to this area

however,he showed no disagreement over the economical disadvantage Teresa mentioned before(that is assume the serious impediment to transporting people into space) and intended to make his point by showing an advantage manned spaceflight has and used the word "definitely",so I think he failed to achieve his position.

in E "national budget" is sth new , not mentioned in the quetion  eliminate

in A B C all of the three indicate that Edward successfully achieve his position and make sense   elininate

open to discuss