Answer:
The correct answer is False.
Explanation:
Once you have selected a crop boundary you can simply press the "Escape" key or the "no" symbol, which cancels the selection.
When you make a selection, everything that is outside of it will be covered with a darker color, this means that it will be discarded.
You can invert the selections, move them or cancel them. You can find these tools by moving the mouse cursor.
You can always change your mind in the area you want to cut, so you will always be allowed to cancel it and start again.
