What does it indicate if an oil is classified as "biologically inert"?

An oil classified as "biologically inert" means that it does not react chemically with skin chemistry. This property is significant because it indicates that the oil will not trigger any adverse reactions or interact negatively with the skin's natural processes. Such oils are often considered safe and suitable for use in skin care products, as they are less likely to cause irritation or allergic reactions.

While some oils may be derived from synthetic sources, this alone does not define their inertness. The classification primarily focuses on the oil's chemical reactivity and compatibility with skin rather than its origin. Low fat content and non-comedogenic characteristics pertain to how an oil may affect skin appearance and pore blockage but do not specifically indicate its reactivity with skin chemistry. Thus, the classification of being biologically inert directly pertains to the absence of reaction with the skin, making option B the most accurate choice.