In this question, you are asked to explain a discrepancy - why are people willing to invest in these technologies, if those investments are so risky? Answer choice (B) does not explain this at all. It just states a fact - that a large variety of these technologies have been developed in the past decade. OK, but why? We are asked to explain why this is so, given how risky investment in these technologies is. Answer choice (A) provides an explanation.
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