How do I "unselect" an option in a dropdown

I have accidentally selected an option in the “owner” field and I need it to remain un-selected for my search to be accurate. But it will not allow me to remove the choice at all. Any suggestions?

You can either start a new search, or you can hold CTRL (PC) or COMMAND (Mac) and click your owner selection and it should deselect it

That worked perfectly!!! Thank you so much