Which compound matches the IR spectrum best?

Answer: The peaks in the IR Spectra are:

a) 3020cm^-1: sp² C-H stretching for benzene

b) 2950cm^-1: sp³ C-H stretching for CH₂ group (alkane)

c)1685cm^-1: C=O stretching for carbonyl group

Among the given structures only B and F qualify. But for B aldehyde C-H stretching at around 2700 -2600 is absent.

So, structure F fits for the IR spectra.