Which of the following is represented by the largest number of species ?

Options

A. Insecta
B. Protozoa
C. Mammalia
D. Aves

Answer

To solve the question "Which of the following is represented by the largest number of species?", we can follow these steps:

### Step 1: Identify the Options
First, we need to identify the options provided in the question. Typically, the options would include different groups or phyla of animals such as Arthropoda, Mollusca, Chordata, etc.

### Step 2: Understand the Phyla
Next, we need to understand the characteristics and the number of species represented by each phylum. For example:
- **Arthropoda**: This phylum includes insects, arachnids, crustaceans, and more. It is known to have the largest number of species, with estimates around 1 million species, primarily due to the class Insecta.
- **Protozoa**: These are single-celled organisms and do not represent a large number of species compared to Arthropoda.
- **Mammalia**: This class includes mammals, which have a relatively smaller number of species compared to Arthropoda.

### Step 3: Compare the Numbers
Now, we compare the number of species in each of the mentioned groups:
- Arthropoda (especially Insecta) has around 1 million species.
- Protozoa has a significantly lower number of species.
- Mammalia has a few thousand species.

### Step 4: Conclusion
Based on the comparison, we conclude that the phylum Arthropoda, particularly the class Insecta, represents the largest number of species.

### Final Answer
Thus, the answer to the question is **option A: Insecta**.

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