South Carolina requires agency disclosure:

Agency disclosure is fundamental to real estate practice as it establishes the legal relationship between agent and client. This question tests knowledge of South Carolina's specific timing requirement for agency disclosure. The core concept is that agency relationships must be established before any substantive brokerage services begin. Option A (At closing) is incorrect because disclosure at closing would be too late - the relationship would have been established without proper disclosure. Option C (Only if requested) is incorrect because disclosure is mandatory, not optional. Option D (Never) is clearly wrong as all states require some form of agency disclosure. The question is straightforward but tests precise knowledge of regulatory timing. This connects to broader real estate principles of transparency, consumer protection, and establishing clear professional boundaries from the outset of any transaction.