This is a test of commonsense with single/multi-choices. Complete the next sentence:

How to remove red wine stains from leather
See if the leather is finished or unfinished.
If the leather is naked or aniline, it has no protective treatment, and will need to be cleaned by a professional. Wet a paper towel, and let one drop of water fall onto the leather.

Options:
(A). Pressing your hand flat, rub the towel gently over the stain, then let the loose drop drop of water land on it. Repeat this step for every stain you want to clean.
(B). This drops the red wine into the stain. If the water does not drop down, it means the wine is almost done.
(C). If it soaks into the leather instantly, do not attempt to clean it yourself. If it remains in a bead on the surface, however, the leather can withstand home treatment.
(D). Let the side of the towel fall so that only one drop lands on the leather. If the towel falls, the dark wine stain will be deeper within the fabric.
The answer is:
(C).