Re: QOTD # 11 The plant called the scarlet gilia can have either									
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									21 Sep 2016, 01:56																	
							 
							
														
								Explanation
The results reported in the last sentence of the passage suggest that hummingbirds do  pollinate  red-flowered  plants  and  that  hawkmoths  do  pollinate  white-flowered plants.  But  to  prove  that  they  are  attracted  preferentially  to  those  colors  requires knowing whether they also pollinate flowers of the other color that are uncovered during  their  respective  foraging  hours—white  flowers  uncovered  during hummingbirds’  daytime  hours,  and  red  flowers  uncovered  during  hawkmoths’ nocturnal  hours. Choice D states that such plants remain unpollinated, so it is the correct  answer.  Of  the  other  options,  both  Choices  C  and  E  could  suggest  the opposite of what is required, so they are incorrect. Choice A is incorrect because the comparative  frequency  at  which  uncovered  gilia  flowers  are  pollinated  has  no bearing on the argument. Likewise, the presence of some quantity of unpollinated flowers of either color does not affect the argument, so Choice B is also incorrect.