When the business of insurance is no longer conducted under an assumed name, an agent...

Detailed Answer in Step-by-Step Solution:

Agents must notify the Virginia Bureau of Insurance (A) of changes like discontinuing an assumed name, as it regulates licensing and business conduct.

The NAIC (B), Chamber (C), and Surety Organization (D) have no direct authority over this requirement.

The Virginia study guide mandates that agents report significant business changes, including assumed name cessation, to the Bureau of Insurance per state law. Reference: Virginia Life, Annuities, and Health Insurance study guide, section on "Agent Responsibilities."