An example of colonial alga is

Options

A. Chlorella
B. Volvox
C. Ulothrix
D. Spirogyra

Explanation

To solve the question, "An example of colonial alga is," we can follow these steps:

### Step 1: Understand the Concept of Colonial Algae
Colonial algae are groups of algae that exist in colonies, where individual cells are connected or grouped together but can function independently. This is different from filamentous algae, which are structured in long chains or filaments.

### Step 2: Analyze the Options Given
The options provided are:
1. Cholera
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