The term closed means made shut, not open, and is c. 1200, past-participle adjective from close (v.). When beginning a cold call, prepare two or three closed-ended questions related to the problem you are proposing to solve. Closed-ended questions allow decision makers to warm up to the conversation and give you the opportunity to have a response prepared for either answer. Open ended questions put the client on the defense too quickly and allow for more thought and a re-direct.
A close opening, doors opening and closing, engaging with fire