Which characteristic is essential for determining how much information can be transferred over optical fiber?

The essential characteristic for determining how much information can be transferred over optical fiber is bandwidth. Bandwidth refers to the capacity of a communication channel to transmit data, specifically the range of frequencies that can be carried over the optical fiber. In optical communications, this bandwidth is typically associated with the amount of data that can be transmitted in a given time period, impacting overall data transfer rates.

Higher bandwidth in fiber optics allows for more data to be transferred simultaneously, enabling higher-speed internet, clearer signals, and the ability to carry more channels of information. This is crucial in applications like high-definition video streaming, cloud computing, and telecommunications, where large volumes of data need to be communicated efficiently.

Resistance, frequency, and voltage do play roles in electrical circuits, but they are not the primary factors in determining the information transfer capabilities of optical fiber. Instead, bandwidth is the defining metric that directly correlates with the amount of information transmitted.