Select the word which means the same as the group of words given.

The therapeutic use of sunlight

heliotherapy

The word that means the same as the group of words "the therapeutic use of sunlight" is heliotherapy.

• Psephology is the study of voting behavior.
• Genealogy is the study of family history.
• Dactylology is the use of fingerspelling to communicate.
• Heliotherapy is the use of sunlight for therapeutic purposes.

The word heliotherapy is the most appropriate because it specifically refers to the use of sunlight to treat medical conditions. The other words do not have the same connotation of medical treatment.