Carpal tunnel syndrome does which of the following?

Carpal tunnel syndrome is a condition that occurs when the median nerve, which runs from the forearm into the palm of the hand, becomes compressed at the wrist. This compression typically leads to symptoms such as pain, numbness, and tingling, primarily in the thumb and the first two fingers (index and middle fingers). These areas are innervated by the median nerve, which is why individuals with carpal tunnel syndrome often report these specific symptoms.

The other options, while related to various conditions affecting the hand and wrist, do not accurately describe carpal tunnel syndrome. Deformities of the joint are more characteristic of other conditions such as rheumatoid arthritis. Acute bursitis relates to inflammation of the bursae and does not directly lead to carpal tunnel syndrome. Finally, inflammation of the forearm extensor tendon pertains to different conditions altogether, such as tendinitis or tendinopathy, and does not fit the description of carpal tunnel syndrome. Thus, the focus on the specific symptoms associated with the median nerve makes the understanding of option A essential for recognizing carpal tunnel syndrome.