Butanedione's reactivity as a 1,2-diketone Steps:

• Butanedione is butane-2,3-dione, with formula CH₃C(O)C(O)CH₃, containing two adjacent ketone groups.
• 2,4-Dinitrophenylhydrazine (DNPH) reacts with any carbonyl (aldehyde or ketone) to form a yellow-orange hydrazone precipitate, so positive test.
• Fehling's reagent oxidizes aldehydes or alpha-hydroxy ketones but not simple ketones or 1,2-diketones, so no reduction and negative test.
• Thus, the reaction profile is positive for DNPH and negative for Fehling's.

Why A is correct:

• 1,2-Diketones like butanedione have carbonyls that form hydrazones with DNPH (positive) but lack the aldehydic H or enolizable structure for Fehling's reduction (negative).

Why the others are wrong:

• B: DNPH test is positive for ketones, not negative.
• C: Fehling's test is negative for non-reducing diketones, not positive.
• D: DNPH test is positive due to carbonyl presence, not negative.

Final answer: A