documentclass{minimal}
usepackage{color}
begin{document}
ABC
end{document}

documentclass{minimal}
usepackage{color}
begin{document}
textcolor{black}{ABC}
end{document}

documentclass{minimal}
usepackage{xcolor}
begin{document}
ABC
end{document}

%%Page: 1 1
TeXDict begin 1 0 bop Black Black 166 83 a Fa(ABC)p Black
Black eop end
%%Trailer

%%Page: 1 1
TeXDict begin 1 0 bop Black Black 0 TeXcolorgray 166
83 a Fa(ABC)p Black Black Black eop end
%%Trailer

%%Page: 1 1
TeXDict begin 1 0 bop 0 TeXcolorgray Black 0 TeXcolorgray
166 83 a Fa(ABC)p 0 TeXcolorgray 0 TeXcolorgray eop end
%%Trailer