GMAT Sentence Correction (SC) | Re: Laboratory rats and mice live up to 40 percent longer than

Hi,

Let me see if I can clear up any ambiguity

Laboratory rats and mice live up to 40 percent longer than usual when fed a dietof at least 30 percent fewer calories than that which they would normally eat, but that otherwise contains all necessary vitamins and nutrients.

(A)of at least 30 percent fewer calories than that which they would normally eat, but that otherwise

Typically 'diet of' is used to describe a specific