The only invertebrates capable of flight belong to the class …………

Explanation

**Step-by-Step Solution:**

1. **Understanding Invertebrates**: Invertebrates are animals that do not possess a backbone. This group includes various classes of animals, such as mollusks, annelids, and arthropods.

2. **Identifying Classes of Invertebrates**: Among the various classes of invertebrates, one class is particularly known for its ability to fly.

3. **Recognizing the Class Capable of Flight**: The class that includes the only invertebrates capable of flight is the class Insecta. Insects are characterized by having a segmented body, exoskeleton, and typically two pairs of wings.

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