The correct structure that corresponds to the spectroscopic data given below is

IR (cm-1): 2720, 1710.

1H NMR: δ9.80 (s, 1H), 7.50 (dd, J = 8.0, 2.0 Hz, 1H), 7.40 (d, J = 2.0 Hz, 1H), 6.90 (d, J = 8.0 Hz, 1H), 3.90 (s, 3H), 3.80 (s, 3H).

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Concept:

Proton Nuclear Magnetic Resonance spectroscopy, as 1H NMR or simply H-NMR, is a powerful analytical technique used in chemistry to determine the structure and purity of organic compounds. It provides information about the hydrogen (proton) atoms in a molecule and their chemical environments. 

Explanation:

In 1H NMR Spectroscopy

  1. δ9.80 - shows CHO group is present in the compound
  2. δ7.50 - shows protons are in deshielded region. CHO is a electron withdrawing group which removes electron density from the neighbouring protons and make them deshielded.
  3. δ3.90 & δ3.80 - shows electronegative group is attached to benzene ring.
  4. dd- H1 will give doublet (d) with Hat ortho position and another doublet (d) with H2 at meta position.

Conclusion :

Hence, the correct structure that corresponds to the following spectroscopic data is 

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