Explanation: Telecommunication cables with multiple pairs use a standardized color code to organize and identify individual wire pairs and larger 25-pair groups. This system simplifies installation, maintenance, and troubleshooting by providing a consistent method for identification. The binder colors for successive 25-pair groups in a larger cable (like a 100-pair cable) follow a specific sequence: * **White** binder: Pairs 1-25 * **Red** binder: Pairs 26-50 * **Green** binder: Pairs 51-75 * **Yellow** binder: Pairs 76-100 Since the question asks for the binder color for pairs 51-75, this corresponds to the third 25-pair group, which is designated by a Green binder. Therefore, Green is the correct answer. Red (B) is for pairs 26-50, while Blue (A) would be for the fifth 25-pair group (pairs 101-125). Black (C) is not a primary binder color for these standard 25-pair groups.