What is the primary characteristic of a documentary film?

A documentary film is primarily characterized by its intention to document reality and convey factual information. Unlike fictional films that are crafted around invented stories and characters, documentaries seek to present real-life events, people, and issues. They rely on actual footage, interviews, and archival material to provide an insight into the subject matter, thus adhering to the principles of truthfulness and authenticity. This commitment to representing reality distinguishes documentaries from other film genres, allowing them to educate, inform, and sometimes persuade audiences on specific topics.

In contrast, the other options focus on aspects that are not intrinsic to documentary filmmaking; entertainment through fiction, fictional narratives, and heavy reliance on visual effects do not align with the primary objectives of documentaries, which are rooted in presenting and interpreting real-world contexts.