C - North to South
The Mekong, Irrawaddy, and Chao Phraya rivers all flow from North to South, thus answering your question.
Hope this helps!
The correct answer is Sea of Japan - answer b) is the correct one!
This sea borders Japan, South and North Koreas, China and Russia.
This sea is named after Japan in most languages, not only in English.
South to it is the East China Sea, which separates China from Taiwan.
