Boiling point of a \( 2\% \) aqueous solution of a non-volatile solute A is equal to the boiling point of \( 8\% \) aqueous solution of a non-volatile solute B. The relation between molecular weights of A and B is:
\( M_A = 4M_B \)
\( M_B = 4M_A \)
\( M_A = 8M_B \)
\( M_B = 8M_A \)