Torque - Propeller rotates one way, plane rotates other way (Newton's 3rd Law)
Spiraling Slipstream - Propwash spirals under the fuselage and strikes the left side of the tail, causing the plane to vear left.
P-Factor - The decending propeller blade has a higher angle of attack to the relative wing, and hence more "lift", causing the right blade to produce more power than the left blade.
Gyroscopic force of the propeller - The propeller acts as a gyroscope, which produces a force 90 degrees from the plane of rotation.
I'm doing this from memory, but I'm pretty sure I got all of them. I'm sure it's fully explained in your training materials; best review that material.
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