All outdoor cables are specifically designed to

• A. Be direct. Buried for ease of installations
• B. Include large numbers of fibers
• C. Prevent rodent damage to the cable
• D. Prevent moisture damage to the fiber

Answer: (D)

Outdoor fiber cables are built to keep water away from the delicate glass fibers. In outdoor environments, moisture is a major threat because water ingress can travel along the cable and increase attenuation, swell materials, and degrade fiber performance over time. To combat this, designers use moisture-blocking barriers, waterproof jackets, and water-blocking gels or tapes inside the cable. This universal focus on preventing moisture damage is what makes moisture protection the best description of how outdoor cables are designed.

Other statements aren’t as universally true: cables can be buried or installed aerially, so ease of installation isn’t the defining feature; the number of fibers varies widely by application, so “large numbers of fibers” isn’t a universal design trait; and while some cables include armor or features to deter rodents, that component isn’t present in all outdoor cables.