Sentence Correction (SC) | Re: Researchers of the Antikythera mechanism claim the retrieval of this a

Usually in everyday speech we use "their" to refer to singular subjects, but GMAT uses their to refer plural subjects
Wrong: Whenevera student calls, take down THEIR information.
Right: Whenevera student calls, take down HIS or HER information.
Right: Wheneverstudents call, take down THEIR information.
(Reference: MGMAT Sentence Correction Guide)
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