Both of them.
Patty, you should be aware that not all houses are good open house candidates.
Most open houses will prove to be a simple demonstration of business, but wholye ineffective in selling your home.
Have a proper analysis completed and implement the marketing strategy most appropriate for your homes location, size and price point.
If an open house is deemed a worthy activity to getting your home sold, you MUST have a plan.
That plan, effectively implemented, is aligned with the needs of the citizens looking for homes in your area. They each have five important deciision to make every year. Zero in on this needs, your homes tangible and intangible assets and your house will most certainly be noticed.
Bake enough cookies for the two visitors, yourself and the agent.