Antonyms – Choose the word that is OPPOSITE in meaning to the highlighted word. Sentence: Many people suffer setbacks in their career because of their inherent levity. Target word: levity

Introduction / Context:
The noun levity denotes lightness of manner, frivolity, or a tendency to treat serious matters with undue humor. In professional settings, excessive levity can be detrimental. The antonym must capture a sober, weighty, responsible attitude in contrast to undue lightness.

Given Data / Assumptions:

• Target word: levity (lightness, frivolity).
• Domain: workplace behavior and careers.
• We need the opposite quality.

Concept / Approach:
Opposites are found by identifying the defining semantic feature. For levity that feature is lack of seriousness. Therefore the antonym will encode gravity, earnestness, or sobriety. Among the choices, seriousness provides the direct opposite without nuance conflicts.

Step-by-Step Solution:
1) Define the pivot: levity = frivolity, trivial lightness.2) Select a term that reverses that quality: seriousness.3) Validate against context: careers normally reward serious, responsible conduct.4) Discard near synonyms of levity to avoid traps.

Verification / Alternative check:
Substitute into the sentence: Replacing levity with seriousness reverses the meaning and remains coherent. Replacing it with any distractor maintains the original sense, confirming they are not antonyms.

Why Other Options Are Wrong:

• frivolity: synonym of levity, not an opposite.
• lightness: overlaps in meaning with levity.
• playfulness: another near synonym in tone and behavior.

Common Pitfalls:
Confusing solemnity or gravity with religiosity or sternness; here the item tests the basic serious versus frivolous contrast, not moral or religious connotations.

Final Answer:
seriousness