Answer:
The correct answer is option c. "increases between its source and mouth".
Explanation:
A stream's discharge is defined as the amount of water that moves from a location to another in a defined period of time. A stream's discharge increases between its source and mouth, which are the origin and the end of the water respectively. This is explained because usually within a stream, the amount of water moves with a steep gradient nears the source and with a gentle gradient once it reaches the mouth.
