Cottage cheese is prepared by using:

Options

A. Lactobacillus
B. Streptococcus lactis
C. Saccharomyces
D. Penicillium

Explanation

**Step-by-Step Solution:**

1. **Understanding Cottage Cheese**: Cottage cheese is a type of fresh cheese known for its creamy texture and soft consistency. It is made from curds of milk.

2. **Identifying Microorganisms**: To determine which microorganism is used to prepare cottage cheese, we need to look at the common bacteria involved in cheese production. The primary organisms involved in the fermentation process of cheese include Lactobacillus and Streptococcus lactis.

3. **Evaluating Lactobacillus**: Lactobacillus is a genus of bacteria that is commonly used in the production of yogurt and other fermented dairy products. However, it is not specifically responsible for the formation of cottage cheese.

4. **Evaluating Streptococcus lactis**: Streptococcus lactis is a type of bacteria that is specifically involved in the fermentation process of milk to produce cottage cheese. It helps in coagulating the milk and forming curds.

5. **Excluding Other Organisms**: Other microorganisms mentioned, such as Saccharomycetes (yeast) and Penicillium (fungus), are not involved in the making of cottage cheese. Saccharomycetes is used in the production of alcoholic beverages, while Penicillium is known for producing antibiotics.

6. **Conclusion**: Based on the evaluation, the correct microorganism used in the preparation of cottage cheese is **Streptococcus lactis**.

**Final Answer**: Cottage cheese is prepared by using **Streptococcus lactis**.

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