Represents the "C" entry of the media rendition dictionary object.

It is an optional entry defined as part of the PDF 1.0 specification.

It contains a MediaClipElement.

For definitive details see:.

The ISO PDF Specification, ISO 32000-1:2008 PDF 1.7; Table: 271, page 491.

The ISO PDF Specification, ISO 32000-2:2017 PDF 2.0; Table: 282, page 615.

The C entry references the media clip dictionary that identifies the source media data, either as an embedded or external file reference with MIME type information.