Question: What is the primary purpose of providing implementors' test data for cryptographic algorithms in 3GPP security specifications?
Option 1: To finalize validation of an implementation's compliance with 3GPP standards.
Option 2: To compare the efficiency of different cryptographic algorithm implementations.
Option 3: To provide a baseline for interoperability testing among various UE (User Equipment) devices.
Option 4: To assist implementors in identifying and debugging errors during their algorithm implementation process.
Explanation: The correct answer, Option 4, reflects the essence of the provided context. The primary purpose of implementors' test data is to aid in the realization of the algorithm specification by providing detailed insights (including input, output, and internal state at various execution stages). This facilitates the identification and rectification of errors during the implementation phase, prior to final validation checks (which are separately defined, as hinted in the context).