The original sentence displays a verb tense error involving a comparison, an ambiguous comparison, and an idiomatic error.
Generations of bees in larval stages have a larger penchant ....than their parents and adult counterparts is an ambiguous and illogical comparison. As written, the sentence can compare how "large" the penchant is that current bees have for dwelling near something to the penchant that their parents and grandparents have, or it can compare how "large" the bees' penchant for dwelling near something to how "large" their penchant is for dwelling near their parents and adult counterparts. The first comparison is more logical. However, the sentence talks about a change regarding what once, in the past, lured pollinators (their parents and adult counterparts) and what now lures the bees in larval stages. The previous penchant should be discussed as one that existed in the past.
"A larger penchant" is unidiomatic. The adjective larger generally describes the size of something. Comparing penchant sizes is unidiomatic.
Choice D fixes the ambiguous comparison in a logical manner. The "change" is described by a logical comparison; a current generation of bees have more of a penchant than older bees had. Describing one group of bees as having more of a penchant for something than another group of bees had is idiomatic.
Choices B and C lack a past tense verb after parents and adult counterparts and thus retain the ambiguous and illogical comparison.
Choice E is awkward and changes the meaning of the sentence. An increasing in the penchant is an awkward phrase and changing than to that eliminates the comparison altogether.
The correct answer is D.
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