Which of the following are the phylum which is the largest (A) and second largest group (B)?

Options

A. A=Insects, B=Molluscs
B. A = Molluscs, B = Insects
C. A = Insects, B = Annelids
D. A = Molluscs, B = Annelids

Explanation

To answer the question regarding the largest and second largest phyla, we can follow these steps:

**Step 1: Identify the largest phylum.**
- The largest phylum in the animal kingdom is **Arthropoda**. This group includes insects, arachnids, crustaceans, and more. It is estimated that about 7 out of every 10 organisms are insects, highlighting the vast diversity within this phylum.

**Step 2: Identify the second largest phylum.**
- The second largest phylum is **Mollusca**. Mollusks are primarily soft-bodied animals, many of which possess a calcareous shell. This group includes snails, clams, octopuses, and squids, and they are mostly found in marine environments.

**Step 3: Summarize the findings.**
- Therefore, the largest phylum (A) is **Arthropoda**, and the second largest phylum (B) is **Mollusca**.

**Final Answer:**
- A: Arthropoda
- B: Mollusca

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