Which of the following refers to the larvae of beetles that are classified in the family Scarabaeidae?

The term for the larvae of beetles in the family Scarabaeidae is "grub." This is a specific designation within entomology, highlighting the life stage of certain beetles as they develop from eggs into larvae. Grubs are typically characterized by their C-shaped bodies and are often found in soil, feeding on organic matter, roots, or decaying material.

Worm does not accurately describe beetle larvae, as it is a broader term that can refer to various types of elongated invertebrates, including earthworms, which are not related to beetles. Caterpillar specifically refers to the larval stage of moths and butterflies, belonging to the order Lepidoptera, and is therefore not applicable to beetles. Pupa refers to the transitional life stage that occurs between the larval and adult forms in many insects, but it does not apply to the larval stage itself, which is correctly identified as a grub in this case.