The correct answer is B. Lactic acid.
Curd is a dairy product produced by coagulating milk with acids or enzymes. The most common way to make curd is to add bacteria to milk, which convert lactose into lactic acid. This process, called fermentation, causes the milk to thicken and separate into curds and whey.
Lactic acid is a sour-tasting organic compound that is produced by the fermentation
of sugars. It is found in many foods, including yogurt, cheese, and sauerkraut. Lactic acid is also produced by the body during exercise.Acetic acid is a colorless, sour-tasting liquid that is found in vinegar. It is also produced by the fermentation of sugars by bacteria. Acetic acid is used in many products, including vinegar, pickles, and salad dressings.
Tartaric acid is a white, crystalline solid that is found in many fruits, including grapes, raspberries, and strawberries. It is also used as a food additive and in the production of baking powder.
Oxalic acid is a white, crystalline solid that is found in many plants, including rhubarb, spinach, and beetroot. It is also used as a cleaning agent and in the production of dyes.
In conclusion, the correct answer is B. Lactic acid.