Which prefix means 'scanty' or 'little'?

The prefix "oligo" is derived from the Greek word "oligos," which means "few" or "little." This prefix is commonly used in various scientific and medical terms to convey the idea of a scarce or insufficient quantity. For example, "oliguria" refers to a condition of producing an abnormally small amount of urine, indicating that the body is experiencing a limited or diminished function in this regard.

In contrast, the other prefixes do not convey the meaning of "scanty" or "little." "Pan" typically refers to "all" or "every," "ex" signifies "out of" or "from," and "epi" means "upon" or "over." Therefore, "oligo" is the most appropriate choice for indicating something that is scanty or little.