Sorts the specified list into ascending order, according to the natural ordering of its elements. All elements in the list must implement the Comparable interface. Furthermore, all elements in the list must be mutually comparable (that is, e1.compareTo(e2) must not throw a ClassCastException for any elements e1 and e2 in the list).
This was brought to my attention and i made corrections to some of the questions quite some time back. The link to the exam was also updated. Feel free to download it from my signature. Yes some people did complain that it was confusing so i removed the option d and changed the answer to e like you have pointed out here. This code will compile and will throw a ClassCastException by the way.