You need to read the given sentence and construct a question about the information present in the sentence. Construct a question in such a way that (i) it is unambiguous, (ii) its answer is unique. The question must involve coreference resolution which is a task of clustering mentions in text that refer to the same underlying real world entities. For example let's take a sentence 'I voted for Obama because he was most aligned with my values, she said.' Here in this example 'I', 'my', and 'she' belong to the same cluster and 'Obama' and 'he' belong to the same cluster. Now let's discuss another example , original sentence: 'I voted for Trump because he was most aligned with my values',John said. Now here is the same sentence with resolved coreferences: 'John voted for Trump because Trump was most aligned with John's values',John said.

Q: Sentence: As Andrea in the crop duster passed over Susan, she could see the landing gear.

A: Who could see the landing gear?
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Q: Sentence: Sam Goodman's biography of the Spartan general Xenophanes conveys a vivid sense of the difficulties he faced in his research.

A: Who faced difficulties?
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Q: Sentence: The doctor informed Kate that she had retired and presented several options for future treatment.

A:
Who had retired?
****
