To "delineate" something means to:

The term "delineate" is derived from the roots related to outlining or defining something in detail. To delineate means to describe or portray something with precision, clarity, and accuracy, effectively creating a clear picture or representation of the subject in question. This action typically involves distinguishing features or characteristics, thereby providing a comprehensive understanding.

For example, in a discussion about a character in a novel, one might delineate their traits and motivations to illuminate their role in the story clearly. This is why the correct choice identifies delineating as a process that involves clear and precise description, as opposed to options that suggest confusion, obscurity, or ambiguity, which directly contrast the clarity and specificity that "delineate" implies.