Icelandic is one of several Germanic languages that is compact when written but can lengthen considerably when translated into English.
b: *translated in English. (wrong preposition)
c: *being translated into English. (passive)
d: *in English translation. (awkward phrasing)
e: *it is written . . . translated in English. (not a parallel construction)
It's a trick question. With one of, you've got a choice, which means you need to use process of elimination to find the correct answer. Click on the link below to read more.