If $x$ is the mass of the gas adsorbed on mass $m$ of the adsorbent at pressure $p,$ Freundlich adsorption isotherm gives a straight line on plotting

• A
  $x/m$ vs $p$
• B
  $x/m$ vs $1/p$
• C
  $\log(x/m)$ vs $\log p$
• D
  $\log(x/m)$ vs $p$