Isogamous condition with non-flagellated gametes is found in

Options

A. Volvox
B. Fucus
C. Chlamydomonas
D. Spirogyra

Explanation

To solve the question regarding which organism exhibits an isogamous condition with non-flagellated gametes, we can follow these steps:

### Step 1: Understand the Types of Gametes
- **Isogamous Condition**: In this condition, both male and female gametes are similar in size and appearance.
- **Flagellated vs. Non-Flagellated Gametes**: Gametes can be either flagellated (capable of movement) or non-flagellated (not capable of movement).

### Step 2: Analyze the Options
- **Bulbox**: This organism is not commonly associated with isogamous reproduction.
- **Fucus**: This organism reproduces via oogamous reproduction, where the female gamete is large and non-motile, and the male gamete is small and motile.
- **Chlamydomonas**: This organism typically has flagellated gametes, which means it does not fit the criteria of non-flagellated gametes.
- **Spirogyra**: This organism reproduces via isogamous reproduction with non-flagellated gametes.

### Step 3: Identify the Correct Answer
After analyzing the options, we find that **Spirogyra** is the organism that exhibits an isogamous condition with non-flagellated gametes.

### Final Answer
The correct answer is **Spirogyra**.

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