Certain enzymes, like those in the Glycogen Breakdown Cascade, are active only when phosphorylated. Suppose you wanted to produce a version of the enzyme that is constitutively active, i.e. active all the time? You can alter the gene and replace a certain:
A. S with K
B. S with T
C. S with E
D. T with R
E. A with B
F. S with A
Answer: C