In the following question, out of the four alternatives, select the one-word substitute that best expresses the meaning of the given phrase: Complete with regard to every detail.

Introduction / Context:
This one word substitution question tests your knowledge of descriptive adjectives used to talk about the quality of work or examination. The phrase “complete with regard to every detail” describes a very careful and detailed approach. You must select the word that accurately sums up this idea in a single term.

Given Data / Assumptions:

• Phrase: Complete with regard to every detail.
• Options: Thorough, Lackadaisical, Lax, Cursory.
• The phrase suggests careful attention to all parts, leaving nothing out.
• We assume we are describing a person's work, investigation or examination of something.

Concept / Approach:
Thorough means done with great care and completeness, paying attention to every detail. It is the standard adjective for work that is detailed, careful and exhaustive. The other options describe the opposite quality: lackadaisical, lax and cursory all suggest carelessness, superficiality or insufficient attention. Therefore, thorough is the only word that matches the positive, detailed meaning of the given phrase.

Step-by-Step Solution:
Focus on the key idea: “complete with regard to every detail” = nothing important is skipped.Recall the meaning of thorough: careful, detailed, and complete in all aspects.Check Lackadaisical: means lazy, lacking enthusiasm and effort.Check Lax: means not strict, careless, or loose in attitude and control.Check Cursory: means done quickly and superficially, without attention to detail.Only Thorough expresses the careful, detailed and complete nature described in the phrase.

Verification / Alternative check:
Replace the phrase with each option in a sentence: “The inspector carried out a complete, detailed check of the equipment.” Changing this to “a thorough check” preserves the meaning. If we say “a lackadaisical check”, “a lax check” or “a cursory check”, we imply that the check was careless or superficial, the opposite of what the original phrase describes. This confirms that thorough is the correct one word substitute.

Why Other Options Are Wrong:
Lackadaisical suggests a lazy, half hearted approach that leaves many details unchecked. Lax indicates weakness in control or enforcement, not detailed completeness. Cursory explicitly means quick and not thorough, making it a near antonym of thorough. Since the question asks for a word meaning complete with regard to every detail, any word implying carelessness must be rejected.

Common Pitfalls:
Students sometimes confuse cursory with curious or similar sounding words, thinking it might be positive. However, cursory always carries a negative sense of superficiality. To avoid confusion, remember the pair thorough vs cursory as opposites: thorough = detailed and complete; cursory = quick and incomplete. With this in mind, it becomes easy to recognise thorough as the best match for “complete with regard to every detail.”

Final Answer:
The one word substitute for “complete with regard to every detail” is Thorough.