Which of the following combining forms would you use in a term pertaining to fatty tissue?

The combining form "lip/o" specifically refers to fat or fatty tissue. This term originates from the Greek word "lipos," meaning fat. In medical terminology, "lip/o" is commonly used in words related to conditions, diseases, and procedures involving fat tissue, such as "liposuction" (surgical removal of fat) or "lipoma" (a benign tumor made of fat tissue).

The other combining forms provided do not relate to fatty tissue. "Kerat/o" pertains to the cornea or hard tissue (often associated with skin or nails), "myc/o" refers to fungi, and "gnos/o" is related to knowledge, particularly in diagnosing conditions. Thus, "lip/o" is the appropriate choice for terms pertaining to fatty tissue, highlighting its relevance in medical contexts regarding fats and lipids.