Choose the appropriate pair of primers to amplify the following DNA fragment by the polymerase chain reaction (PCR).
$$\textrm{5’ – GACCTGTGG- – – – – – – – – – – – – – – – – – ATACGGGAT – 3'}$$
$$\textrm{3’ – CTGGACACC – – – – – – – – – – – – – – – – – – TATGCCCTA – 5’}$$
$$\begin{array}{ll} & \textbf{Primers} \\ P. & \textrm{5’ – GACCTGTGG – 3’} \\ Q. & \textrm{5’ – CCACAGGTC – 3’} \\ R. & \textrm{5’ – TAGGGCATA – 3’} \\ S. & \textrm{5’ – ATCCCGTAT – 3’} \end{array}$$
- $P$ and $R$
- $P$ and $S$
- $Q$ and $R$
- $Q$ and $S$