Combining form indicating relationship to the thymus?

• A. Thym/o
• B. Histo/o
• C. Lingu/o
• D. Onc/o

Answer: (A)

Thym/o signals a relationship to the thymus, the immune system organ in the chest where T cells mature. In medical terms, combining forms link a root to suffixes to form words about a specific organ or structure, so thym/o- is used when talking about the thymus. That makes it the best choice for indicating a relationship to the thymus, as in thymopathy or thymitis, or when forming thymectomy (removal of the thymus).

Other roots point to different ideas: histo- means tissue, lingu- means tongue, and onc- refers to tumors. They don’t convey a connection to the thymus, which is why thym/o is the correct pairing here.