$Group\; I$ lists spectroscopic methods and $Group\; II$ lists biomolecular applications of these methods. Match the methods in $Group\; I$ with the applications in $Group\; II$.

$$\begin{array}&&\textbf{Group I} & \textbf{Group II} \\ &\text{P. Infrared} & \text{1. Identification of functional groups}\\ &\text{Q. Circular Dichroism} & \text{2. Determonation of secondary structure} \\ &\text{R. Nuclear Magnetic Resonance} & \text{3. Estimation of molecular weight} \\ &\text{} & \text{4. Determination of 3-D structure} \\ \end{array}$$

1. $P-4, Q-3, R-1$
2. $P-2, Q-1, R-3$
3. $P-1, Q-2, R-4$
4. $P-3, Q-2, R-4$