Which word describes something that is complete and includes everything?

The word that best describes something that is complete and includes everything is "comprehensive." This adjective conveys a sense of thoroughness and completeness, indicating that all aspects or details are covered. For example, a comprehensive curriculum would include all necessary subjects and skills, ensuring that students receive a well-rounded education.

In contrast, the other options do not align with the idea of completeness. "Ambiguous" refers to something that is unclear or open to multiple interpretations, which directly opposes the clarity and thoroughness implied by "comprehensive." "Ubiquitous" means present everywhere at the same time, which does not necessarily convey the idea of completeness or inclusion. "Theoretical" pertains to ideas or principles that are abstract or not practically applied, rather than describing something that encompasses all aspects in a concrete manner. Thus, "comprehensive" is clearly the term that encapsulates the essence of being complete and inclusive.