Answer:
B. Northwest
Explanation:
Looking at elevation it is higher up on the bottom of the map, and the elevation lowers as we go north. Therefore we can conclude the river is flowing northwards, and since we have ruled out that higher elevation means the river is not flowing towards it, then northeast is also not valid. There is no river to the east and therefore we must conclude that Northwest is the answer.
(Figured you would prefer an explanation other than just 'Northwest')
