What is the conjugate base of phenol, \({{\text{C}}_{\text{6}}}{{\text{H}}_{\text{5}}}{\text{OH}}\)?

A.     \({{\text{C}}_6}{\text{H}}_4^ - \)–OH

B.     \({{\text{C}}_6}{{\text{H}}_5}\)–\(\mathop {\text{O}}\limits^ +  {{\text{H}}_2}\)

C.     \({{\text{C}}_6}{{\text{H}}_5}\)–\({{\text{O}}^ - }\)

D.     \({{\text{C}}_6}{\text{H}}_6^ + \)–OH

C