Final answer:
Infrared spectroscopy excels at detecting functional groups such as aldehydes and alcohols due to their characteristic and strong IR absorption patterns, especially the carbonyl group in aldehydes.
Step-by-step explanation:
Infrared spectroscopy is particularly effective at identifying functional groups in organic compounds because different groups absorb at characteristic frequencies. For instance, the carbonyl group in aldehydes and ketones typically absorbs strongly due to its polar nature, in a distinctive range around 5.11 - 5.18 x 10¹³ Hz. In contrast, alkanes are generally less reactive and have less distinct absorption patterns in IR spectroscopy. Therefore, between the options given, infrared spectroscopy is particularly good at detecting functional groups such as aldehydes (B) and alcohols (D) due to their distinct and strong IR absorption patterns. Aldehydes have a carbonyl group that absorbs strongly, which makes them easily identifiable in an IR spectrum.