CATV coax cable is constructed with a(n) ___ shield.

The correct answer identifies that CATV coax cable typically has an aluminum shield due to a variety of advantageous properties associated with aluminum. Aluminum offers excellent conductivity while being lighter and less expensive than copper, making it a preferred choice for shielding in many coaxial cables.

The aluminum shield effectively protects the inner conductor from electromagnetic interference (EMI) and contributes to the overall durability of the cable, helping maintain signal quality over long distances. Aluminum also has good corrosion resistance, which enhances the longevity of the cable in varying environmental conditions.

While coax cables can also utilize copper or even steel in some designs, aluminum remains the most common material used for shielding in CATV applications specifically due to its balance of performance, weight, and cost.