The compound shown is treated with one equivalent of base. Which hydrogens are removed, and how many resonance structures (counting the carbanion form and enolate forms with complete octets) does the conjugate base have?

1. Athe CH2 hydrogens between the carbonyl groups; 3 structures
2. Bthe CH2 hydrogens between the carbonyl groups; 2 structures
3. Cthe CH3 hydrogens of the acetyl group; 2 structures
4. Dthe OCH3 hydrogens; 1 structure