please help complete a b and c it is all one question

3) A researcher performed the following mono-acetylation of the tetraol below to give only one product. Using the 'H NMR on the next page, determine which of the 4 possible products was formed. . - HOAC . - Bu2Sno, Aco - OAC DMF Ac - a) What signal allowed you to determine the correct structure? How did it allow you to determine the product? b) Circle the product that was formed. c) What kind of multiplet is at 1.7 ppm? Give your answer in the standard format 86.57 (dtd, 12, 6, 2 Hz, 1H). SR 250 ST- BIBBO CHO EDO MHESH NMR 869 HAAN SIT HHH SW uhu 440 4405 pom 3.57 3.54 3.51 3.48 3.45 3.42 3.39 3.36 3.33 ppm BIG CO 1.918 104 MOT 1.680 1. LE OT 1862 1.858 SSRT 1.652 1.048 1.142 1729 1.725 1.712 1.706 1.200 1.699 11.636 1.600 1680 1.683 wurthy 2.10 2.0 2.06 2.04 2.02 2.00 1.96 1.96 1.94 1.92 1.90 1.88 1.86 1.84 1.82 1.80 1.78 1.76 1.74 1.72 1.70 1.68 1.66 1.64 ppm 2.04 1.00 Strona Lane AA ma