What area of study focuses primarily on moths?

The area of study that focuses primarily on moths, as well as butterflies, is Lepidoptery. This branch of entomology is specifically dedicated to Lepidoptera, the order of insects that includes both moths and butterflies. Lepidopterists dedicate their research to the life cycles, habitats, behaviors, and conservation of these insects, making it the most relevant field for studying moths.

Entomology, while a broader field that encompasses the study of all insects, does not specifically focus only on moths. Ornithology pertains to the study of birds and is entirely unrelated to moths, while botany is the study of plants, further setting it apart from the focus on insects. Thus, the correct choice is clearly Lepidoptery for its direct connection to the study of moths.