In an agency to sell real property which of the following renders the authority and contract of sale valid?

• A. General power of attorney, granting the agent authority to sell real property, not put into writing.
• B. General power of authority put into writing without authority to sell.
• C. A special power of attorney put into writing authorizing the agent to sell real property of the principal.
• D. Special power of attorney couched in general terms without referring to specific acts of dominion.