Explanation: The Global Positioning System (GPS) operates in the L-band of the radio spectrum, transmitting precise timing and navigation signals from satellites to Earth. The primary frequencies are L1 at 1575.42 MHz and L2 at 1227.60 MHz. The L1 frequency carries the Coarse/Acquisition (C/A) code, which is available for civilian use, and the encrypted P(Y) code. The L2 frequency primarily carries the P(Y) code and newer civilian signals like L2C, which allow for ionospheric error correction and improved accuracy. These frequencies are specifically allocated and optimized for satellite navigation, offering good propagation characteristics through the atmosphere while minimizing delays and interference. The other options list frequencies that are not part of the standard GPS signal structure.