A student prepares a buffer solution for a biological assay by combining
(\text{NaH}_2\text{PO}_4\text{(aq)}\) and \(\text{Na}_2\text{HPO}_4\text{(aq)}\). The \(\text{pH}\) of the resulting solution is measured to be \(8.20\) at \(25\ ^\circ\text{C}\). Acid-dissociation constants for phosphoric acid at \(25\ ^\circ\text{C}\) are provided in the table below.

Acid	Dissociation Reaction	\(pK_a\)
\(\text{H}_3\text{PO}_4\)	\(\text{H}_3\text{PO}_4\text{(aq)} + \text{H}_2\text{O}\text{(l)} \rightleftharpoons \text{H}_3\text{O}^+\text{(aq)} + \text{H}_2\text{PO}_4^-\text{(aq)}\)	\(2.12\)
\(\text{H}_2\text{PO}_4^-\)	\(\text{H}_2\text{PO}_4^-\text{(aq)} + \text{H}_2\text{O}\text{(l)} \rightleftharpoons \text{H}_3\text{O}^+\text{(aq)} + \text{HPO}_4^{2-}\text{(aq)}\)	\(7.20\)
\(\text{HPO}_4^{2-}\)	\(\text{HPO}_4^{2-}\text{(aq)} + \text{H}_2\text{O}\text{(l)} \rightleftharpoons \text{H}_3\text{O}^+\text{(aq)} + \text{PO}_4^{3-}\text{(aq)}\)	\(12.32\)

Based on this information, which of the following is the value of the ratio \(\dfrac{[\text{HPO}_4^{2-}]}{[\text{H}_2\text{PO}_4^-]}\) in the buffer solution?