Which of the following segments of the integral membrane protein glycophorin most likely contains the membrane-spanning sequence?
A) LSTTEVAMHTTTSSSVSKSY
B) SQTNDTHKRDTYAATPRA
C) VSEISVRTVYPPEEETGE
D) ITLIIFGVMAGVIGTILLI
E) YGIRRLIKKSPSDVKPLP
Answer: D) ITLIIFGVMAGVIGTILLI