This question calls for diagramming. Here's an outline of the argument:
Remain competitive in economy - -> overcome crisis in math Overcome crisis in math - - > employ successful teaching methods Successful teaching methods - -> students study outside class
Now turning to the answer choices:
(A) is incorrect because it reverses the logic. It says that if students study outside - -> then we'll overcome the crisis in math. This combines the premises backwards.
(B) is correct. It diagrams to: overcome crisis in math - -> students study outside class. This simply combines premises 2 and 3 and therefore it follows logically from the premises.
(C) is incorrect because it is irrelevant.
(D) is incorrect. It diagrams to: students study outside class - -> remain competitive in economy. This is the reverse logic of the argument.
(E) is incorrect. The argument tells us that we can only remain competitive if students spend time studying math outside class. This answer choice tells us that we will definitely remain competitive if students spend time studying math outside class. These are not the same thing, and therefore the answer choice can't be inferred from the premises.