What is the function of a cable shield?

The function of a cable shield is primarily to prevent interference, which is why the choice indicating that is correct. A cable shield surrounds the inner conductor of the cable and acts as a barrier against electromagnetic interference (EMI) and radio frequency interference (RFI) from external sources. This shielding helps to maintain the integrity of the signals being transmitted through the cable, ensuring that external noise does not disrupt the communication or data being carried.

Effective shielding is crucial in various applications, particularly in environments with high levels of electrical interference, such as near heavy machinery or radio transmitters. By minimizing signal degradation and maintaining signal quality, the shield enhances the overall performance and reliability of the cabling system.

The other options, while related to cable design and function, do not accurately describe the primary purpose of a cable shield. Insulation pertains to preventing electrical contact and ensuring safety, increasing conductivity refers to improving the flow of electrical current, and supporting structural integrity is more about the physical strength of the cable rather than its electromagnetic capabilities.