Liquid $A$ and $B$ form an ideal solution. The vapour pressure of pure liquids $A$ and $B$ are $350 \ mm \ Hg$ and $750 \ mm \ Hg$ respectively at the same temperature. If $x_A$ and $x_B$ are the mole fractions of $A$ and $B$ in the solution,and $y_A$ and $y_B$ are the mole fractions of $A$ and $B$ in the vapour phase,then:

• A
  $\frac{x_A}{x_B} < \frac{y_A}{y_B}$
• B
  $\frac{x_A}{x_B} = \frac{y_A}{y_B}$
• C
  $\frac{x_A}{x_B} > \frac{y_A}{y_B}$
• D
  $(x_A - y_A) < (x_B - y_B)$