Match the following attributes of a city with the appropriate scale of measurements.

$$\begin{array} {|l|l|} \hline \qquad \qquad \qquad \textbf{Attribute} & \textbf{ Scale of measurement} \\\hline \text{(P) Average temperature} \; (^\circ \text{C) of a city} & \text{(I) Interval} \\\hline \text{(Q) Name of a city} & \text{(II) Ordinal} \\\hline \text{(R) Population density of a city} & \text{(III) Nominal} \\\hline \text{(S) Ranking of a city based on ease of business} & \text{(IV) Ratio} \\\hline \end{array}$$

Which one of the following combinations is correct?

1. $\text{(P)-(I), (Q)-(III), (R)-(IV), (S)-(II)}$
2. $\text{(P)-(II), (Q)-(I), (R)-(IV), (S)-(III)}$
3. $\text{(P)-(II), (Q)-(III), (R)-(IV), (S)-(I)}$
4. $\text{(P)-(I), (Q)-(II), (R)-(III), (S)-(IV)}$