PT 58 S4 Q1

Automated flight technology can guide an aircraft veryreliably, from navigation ... ...

Which one of the following, if true, most helps to explain the situation described above?
(A) Automated flight technology does not always function correctly.
(B) ...
(C) ...
(D) ...
(E) ...

*This question is included in Complete Section: LR-B, Sept. '09 LSAT (PT 58 Sec. 4)