A patient presents with a deficiency in the activation of pancreatic zymogens. If the enzyme responsible for the initial activation step is absent, which of the following processes will be primarily impaired?

1. A.Conversion of $\text{trypsinogen}$ to $\text{trypsin}$ by $\text{enterokinase}$
2. B.Hydrolysis of starch by $\text{salivary amylase}$
3. C.Emulsification of fats by $\text{bile salts}$
4. D.Absorption of ${\text{vitamin B}}_{12}$ in the ileum