Four elements P, Q, R and S belong to groups 13, 15, 16, and 17, but not in that order. The electronegativity values of four elements in the same period of the periodic table are listed below:

Question

$\begin{array} {llll} P & Q & R & S\\ 3.0 & 2.0 & 3.5 & 4.0 \\ \end {array}$

Based on this information, which element belongs to which group?

$\begin{array}{1 1} P = 13 Q = 15 R = 16 S = 17 \\ P = 15 Q = 13 R = 16 S = 17 \\ P = 15 Q = 13 R = 17 S = 16 \\ P = 13 Q = 16 R = 15 S = 17 \end{array}$