In the question, a sentence is given with four highlighted parts, in which only one highlighted part of the sentence is incorrect. In the given options the correct part of the sentence is mentioned, you have to identify which of the part need improvement and mark it as your answer. The best hope for the challenger is to invest heavily on research and development, build a parallel ecosystem, and then wait for a fresh technological wave that would destroy the incumbent and allowed the challenger a fresh impetus to lock in its own set of products