The three microbes are listed below. Name the product produced by each one of them and mention their use.
(a) Aspergillus niger
(b) Trichoderma polysporum
(c) Monascus purpureus

Explanation

To answer the question regarding the three microbes, their products, and their uses, we can break it down step by step:

### Step-by-Step Solution:

1. **Identify the first microbe: Aspergillus niger**
- **Product Produced:** Citric Acid
- **Use:** Citric acid is widely used in the food and beverage industry as a flavoring agent and preservative. It is also used in the production of gluconic acid and in various industrial applications.

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