-graph meaning

• A. Glucose
• B. Tongue
• C. Written, recording
• D. Knowledge

Answer: (C)

The meaning being tested is the sense of the suffix -graph: it denotes something that writes, records, or a device that records. In medical and scientific terms you see it used for instruments or results that produce a written or traced record, such as an electrocardiograph (records heart activity) or a radiograph (an X-ray image). Therefore, the meaning that fits is “written, recording.” Glucose is a sugar, tongue is a body part, and knowledge is information—none of these relate to writing or recording like -graph does.