Consider three metal chlorides $x$, $y$ and $z$, where $x$ is water soluble at room temperature, $y$ is sparingly soluble in water at room temperature and $z$ is soluble in hot water. $x$, $y$ and $z$ are respectively:

• A
  $MgCl_{2}$, $AgCl$ and $AlCl_{3}$
• B
  $AgCl$, $Hg_{2}Cl_{2}$ and $PbCl_{2}$
• C
  $AlCl_{3}$, $PbCl_{2}$ and $BaCl_{2}$
• D
  $CuCl_{2}$, $AgCl$ and $PbCl_{2}$