the dr couple

[maihuna]

Clark and Florence Wallace, a husband-and-wife medical team, worked steadily and efficiently through the night, but sipping their coffee the next morning, she noticed that he seemed disoriented.
(A) sipping their coffee the next morning, she noticed that he seemed disoriented
(B) sipping their coffee the next morning, he seemed to be disoriented, she noticed
(C) as they sipped their coffee the next morning, she noticed that he seemed disoriented
(D) as they were sipping their coffee the next morning, he seemed, she noticed, disoriented
(E) he seemed disoriented, she noticed, sipping their coffee the next morning

[kc_raj]

IMO C

A, B their is incorrect pronoun "their" seems to refer to he or she

in C as they sipped their coffee is absolute modifier

D, E reads awkward, in E their refers to what is not clear