🤓 Based on our data, we think this question is relevant for Professor Paddock's class at UCSD.

Solution: Consider the following compound whose protons are labeled as a, b, c, d and e. Its   1H NMR spectrum is also shown below. Circle the proton that shows a quintet at δ3.55 ppm.  

Problem

Consider the following compound whose protons are labeled as a, b, c, d and e. Its   1H NMR spectrum is also shown below. Circle the proton that shows a quintet at δ3.55 ppm.