Out of phenol and benzene, which can be more easily nitrated ?
A. presence of `-OH` group in phenol increases the electron density at ortho and para-position
B. presence of `-OH` group in phenol decreases the electron density at ortho and para-position
C. nitration being electrophilic sustitution requires less density at ortho and para-position
D. phenol is more reactive than benzene due to -R effect .