Correct choice is (a) \(\tilde{\phi_f}=\tilde{\phi_c}+\frac{1}{4}\)
Explanation: The relationship between Φf and Φc is
\(\phi_f=\phi_c+\frac{1}{4}(\phi_D-\phi_U)\)
The normalized forms of Φf, Φc, ΦD and ΦU are \(\tilde{\phi_f}, \tilde{\phi_c},\) 1 and 0 respectively. Therefore,
\(\tilde{\phi_f}=\tilde{\phi_c}+\frac{1}{4}.\)