The strong reducing property of hypophosphorus acid is due to

• A

  the positive valency of phosphorus
• Correct answer
  B

  two $\mathrm{P}-\mathrm{H}$ bonds
• C

  presence of phosphorus in its highest oxidation state
• D

  its concentration

Solution

The strong reducing property of hypophosphorus acid is due to the presence of two $\mathrm{P}-\mathrm{H}$ bonds. Its structure is as follows

Hence, the correct answer is option: 'B'.