Helium, a non renewable by-product of natural gas, is vital

I am not so sure about the source of this question. Sure, I could tell you why (C) is the best answer, but we always want to make sure we are using reputable sources so that our brains are trained to think in the way that GMAT does. Now, why do I think the source is suspect. Well, it misses some basic grammar points.
(and I don't think they are all typos ).

Helium, a non renewable by-product of natural gas, is vital to the development of superconductor and other technology that are now emerging and will be important in the future. Yet helium is being wasted when natural gas is extracted because of a lack of storage space for the helium. Because helium is being wasted (NEEDS A COMMA), THE US industry will not have enough of the commodity when it needs it in the future.

Which of the following, if true, would cast the most doubt on the accuracy of the prediction above?

A) In the US, the market price of the (OMIT 'THE') natural gas is rising sharply, while the market price of the (OMIT 'THE') helium remains unchanged.

B) The US government now maintains strategic stockpiles of helium so that some helium will be conserved for military uses.

C) Recently discovered uses for helium can be expected to raise helium's price to the point where it will soon be economical to build excess storage capacity for helium in the US.

So yes, I suppose this works best, but it is weak. First off, we have to assume that 'can be expected' means most likely. Even the 'soon' is weak. My hunch is GMAT would have phrased this answer choice very differently. And so that's why it's important to use GMAT material when possible--to get a sense of the way the correct answer is worded. Plus the basic grammatical errors leads me to think this source is best avoided.

D) The number of newly discovered large natural gas deposits in the US has been declining each year for the past 5 years.

E) Recently discovered superconductor (NEED A PLURAL 'S') that work at temperatures well above absolute zero have not been developed to the point where they are fully practical.