Which of the following suffixes is commonly used to indicate a condition of weakness?

The suffix "-asthenia" is derived from the Greek word "astheneia," which means weakness. It is specifically used in medical terminology to denote a condition characterized by a lack of strength or reduced ability to function normally. This suffix is often combined with other word roots to describe specific types of weakness, such as muscle weakness (myasthenia) or general fatigue (asthenia).

In contrast, the suffix "-itis" refers to inflammation, commonly used in the names of conditions such as arthritis (inflammation of the joints) or dermatitis (inflammation of the skin). The suffix "-pathy" signifies a disease or condition, like neuropathy, which refers to a disease affecting the nerves, but does not specifically denote weakness. Similarly, "-emia" pertains to a condition related to blood, as seen in terms like anemia (a deficiency in the number of red blood cells) but does not imply weakness directly. Thus, "-asthenia" is the most appropriate suffix to indicate weakness.