Which of the following oxoacids of phosphorus has strongest reducing property?

Step-by-step solution

P - H bonds found in phosphorus acids have reducing properties. Thus, reducing property is directly proportional to number of P - H bonds. The structures of given oxoacids of phosphorus are as follows: H ₃ PO ₂ contains 2 P - H bonds which is maximum among given options. Thus, H ₃ PO ₂ has strongest reducing property.