Spiders and scorpions belong to________class under phylum Arthropoda.

Explanation

**Step-by-Step Solution:**

1. **Identify the Phylum**: The question states that spiders and scorpions belong to the phylum Arthropoda. This is the first step in understanding their classification.

2. **Recognize Key Characteristics**: Spiders and scorpions share certain characteristics that distinguish them from other arthropods. They do not have antennae, claws, or wings.

3. **Understand Body Structure**: In spiders and scorpions, the head and thorax are fused into a single structure known as the cephalothorax. This is a significant feature that helps in their classification.

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