What is the difference between a partial stall and a full stall? I have this study question on the FIA written:

Which statement is true concerning the aerodynamic conditions which occur during a spin entry?

Correct Answer: After a full stall, the wing that drops continues in a stalled condition while the rising wing regains and continues to produce some lift, causing the rotation. 

Incorrect Option: After a partial stall, the wing that drops remains in a stalled condition while the rising wing regains and continues to produce lift, causing the rotation. 

Because the only difference between the two answer options is 'full' and 'partial' I was wondering what are the differences between a full stall and a partial stall?
For GA aircraft with straight, rectangular wings, the stall usually starts at the root and progresses towards the tip. So, at some point, only a portion of the wing will be stalled. This is sometimes referred to as partial stall, though it is not a common term.



Image from boldmethod.com

This is usually achieved by having a washout or a wing cuff. In case of root-first stall, the wing tips are still producing lift, helping to prevent rolling motion (which may occur if the whole wings stalls at once), which in turn prevents the aircraft from entering a spin.