You Are Working with an Enzyme Altase That You Denature

You are working with an enzyme altase that you denature in the presence of urea. If altase were denatured no further by the addition of mercaptoethanol, what would that suggest to you about the enzyme?

A) The enzyme probably contained no positively charged amino acids since these are neutralized by mercaptoethanol.
B) The enzyme probably contained no acidic amino acids since these are neutralized by mercaptoethanol.
C) The enzyme probably contained no disulfide linkages since mercaptoethanol breaks such linkages.
D) Mercaptoethanol and urea denature enzymes in the same manner, so the observation lacks significance.