### Instruction: What are the primary grapes in a red Bordeaux?
### Input: Red Bordeaux is generally made from a blend of grapes. Permitted grapes are Cabernet Sauvignon, Cabernet Franc, Merlot, Petit Verdot, Malbec and Carménère. Today Carménère is rarely used, with Château Clerc Milon, a fifth growth Bordeaux, being one of the few to still retain Carménère vines. As of July 2019, Bordeaux wineries authorized the use of four new red grapes to combat effects of climate change on viticulture in Bordeaux. These newly approved grapes are Marselan, Touriga Nacional, Castets, and Arinarnoa.
### Response: Cabernet Sauvignon, Cabernet Franc, Merlot, Petit Verdot, Malbec