Final answer:
The text provided does not include an encrypted message or encryption details, so it is not possible to decrypt it. Therefore, the correct answer is 'b) Insufficient information'.
Step-by-step explanation:
The question provided is insufficient to determine Sandra's birth date since no actual encrypted message was included in the provided text. To decrypt a message, one would require specific information about the encryption method used, and any relevant keys or algorithms necessary for the process. Without these details or the actual encrypted text, it is impossible to proceed with decryption.
Thus, the correct answer from the given options would be 'b) Insufficient information', as we lack both the encrypted message and the method of encryption needed to uncover Sandra's birth date.