Which voice-grade UTP cable category is capable of supporting transmission rates of up to 100 Mbps?

The choice of Cat 5 cable is correct because it is specifically designed to support data transmission rates of up to 100 Mbps. Cat 5 cables utilize twisted pair wiring, which helps reduce crosstalk and allows for efficient transmission of data over the network. This category of cable was commonly used in Ethernet networks and supported a range of applications, making it a standard in networking.

In contrast, Cat 1 cables are primarily used for voice communications with no capability for data transmission, while Cat 4 cables support speeds between 8 Mbps and 20 Mbps, which is lower than what Cat 5 offers. Cat 6 cables, while superior and able to support higher speeds (up to 10 Gbps), are not the correct answer for the specified range in the question. Therefore, Cat 5 is the accurate selection for supporting transmission rates up to 100 Mbps.