Final answer:
The legal act that would not be grounds for revoking a broker's license in NH is agreeing to accept a listing at more than the usual commission rate. Other options involve fraudulent or unethical behaviours that would justify revocation.
Step-by-step explanation:
In the context of real estate brokerage laws in New Hampshire (NH), the only option among those presented that is legal and not grounds for revoking a broker's license is D. Agreeing with a seller to accept a listing more than the broker's usual commission rate. This practice is considered legal because commission rates are typically negotiable between a broker and their client. The other options, such as A. Being convicted of obtaining money under pretences, B. Advertising falsely that one is a member of a professional association, and C. Depositing escrow money in one's account, are all actions that violate professional ethics and regulations in the real estate industry and can lead to license revocation.