ummmmmmmmmmmmmm eh heh heh alrighty help me

which one!
the movement of the river through easily erosed rocks or sediment
the erosion of rock where a river flows over it and erodes the softer rock

for this question
Which causes a meander to form in a river?

The answer is the erosion of rock where a river flows over it and erodes the softer rock. This causes the river to form a meandering pattern as it flows.

its the first one right?