Rivier is the guy who thinks the protagonist does what he thinks is a choice but is really a path already laid out by the gods.
Eliminate:
A: no mention of the gods.
B: same as A
C: disobey gods? then this means the protagonist makes a choice against the wishes of the gods.
D: same as C
Choose:
E: Correct! "no alternative" and "course chosen by the gods" match our prephrase. ALSO, just because the figure follows the course chosen by the gods, doesn't mean he acknowledges that the path was chosen by the gods.