ExplanationTo fill in the blank, you need to identify what the professor did to the exam question. Because he or she reordered the sentences and added distractions, he or she made the problem more confusing and unclear.
Muddled and obfuscated are synonyms that mean made obscure or unclear and are therefore the correct choices. Erased and obliterated are also synonyms, but do not describe what the professor did to the question. Interpreted means made clear, which is the opposite of what the professor did. Engendered is a nice vocabulary word but means produced or caused, which has nothing to do with making a previously created problem confusing.
Hence options B and F are correct!
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