2. The diagram below represents the chemical pathway of a process in a human liver cell.
A particular liver cell is unable to make substance C. One possible explanation for the inability of this cell to make substance C is that
A.)nuclear DNA was altered resulting in the cell being unable to make enzyme
Y
B.)an excess of enzyme X was present, resulting in a decrease in the
production of substance B.
C.) excess energy for step 2 prevented the conversion of substance B to
substance C.
D.) a mutation occurred causing a change in the ability of the cell to use
substance C.