Compound A (C11H16O) has a band in the IR spectrum at 3450 cm-1 (strong, broad) and does not react with pyridinium chlorochromate (PCC) in CH2Cl2. Compound A does react with HBr to give compound B (C11H15Br). Compound B reacts with potassium t-butoxide to give compound C (C11H14). Ozonolysis of C followed by treatment with Zn and water gives CH3CHO and compound D (C9H10O). The proton NMR spectrum of compound D is given below. Treatment of compound D with ethyl magnesium bromide yields A. Draw the structures of compounds A, B, C, and D. 1H NMR of D: ? 8.1-7.5, multiplet, 5H; 2.85, quartet, 2H; 1.30, triplet, 3H.