The hook-like structures found on the abdominal prolegs of endopterygote (lepidopteran) larvae are known as:

✅ Explanation: In the endopterygote larvae of lepidopterans (such as caterpillars), the hook-like structures on the abdominal prolegs are called crochets. These crochets help the larvae grip onto surfaces, allowing them to anchor themselves securely while feeding or resting.

📌Other Options Explanations:
Tarsi: The foot segments of an insect leg.
Cerci: Paired appendages at the end of the abdomen, often sensory in function.
Taenidia: Spiral thickenings in the tracheal tubes of insects that help keep them open.