To name a plane that contains AC, one would usually have three non-collinear points in a geometric drawing such as a triangle ABC, after which the plane can be named plane ABC. Without additional context or a drawing, it can't be named specifically.
Naming a plane that contains a line segment AC in geometry typically involves referencing a drawing or specific figure. In geometry, planes are often named by three non-collinear points lying on the plane or designated by a capital italicized letter. For instance, in the context of a triangle ABC, the plane can be denoted as plane ABC.
However, in the absence of a drawing or additional context, providing a specific name for the plane containing AC becomes challenging. In such cases, if only one plane is under consideration in a problem or figure, it might be referred to simply as 'the plane' or represented by a single letter, such as plane P. The specific nomenclature often depends on the clarity and requirements of the geometric representation at hand.