Question

Which one is correct for S.I. units?

They do not change with place or time

Different countries follow different S.I. units

They are adopted from F.P.S system​

Answer 1

$\large\mathscr \color{black}\colorbox{red}{\colorbox{orange}{\colorbox{yellow}{\colorbox{green}{\colorbox{blue}{\colorbox{indigo}{\colorbox{violet}{\underline {ANSWER}}}}}}}}$

$\large\tt\bold\color{red}{They\:do\:not\:change\:with\:place\:or\:time_¤}$