Which are the driest wines?

[Charmayne]

My mother is on a new diet in which she has cut her carbohydrates down, and the diet allows for only the driest wines. She currently drinks mainly Cabernet Sauvignon, but she'd like the names of some other wines that are drier. If anyone has any information, please email me at Charmayne7@aol.com. Thanks in advance for your help.