The compound(s) with P – H bond(s) is(are)

To determine which compound(s) contain P - H bond(s), let us analyze the structures of the given oxyacids of phosphorus:
1. Orthophosphoric acid ($H_{3}P{O}_4$):
In orthophosphoric acid, the central phosphorus atom is bonded to three -OH groups and one oxygen atom via a double bond (P=O). The structure is:
O=P(OH)₃
Here, all three hydrogen atoms are bonded to oxygen atoms as -OH groups. There are no direct P - H bonds in $H_{3}P{O}_4$.

2. Phosphonic acid / Phosphorous acid ($H_{3}P{O}_3$):
In phosphorous acid, the central phosphorus atom is bonded to one oxygen atom via a double bond (P=O), two -OH groups, and one hydrogen atom directly. The structure is:
O=PH(OH)₂
Thus, $H_{3}P{O}_3$ contains one P - H bond.

3. Pyrophosphoric acid ($H_4{P}_2{O}_7$):
Pyrophosphoric acid consists of two phosphoric acid units linked by a P - O - P anhydride bridge. Each phosphorus atom is also bonded to one double-bonded oxygen and two -OH groups. The structure is:
(HO)₂P(=O) - O - P(=O)(OH)₂
There are no direct P - H bonds in $H_4{P}_2{O}_7$.

4. Phosphinic acid / Hypophosphorous acid ($H_{3}P{O}_2$):
In hypophosphorous acid, the central phosphorus atom is bonded to one oxygen atom via a double bond (P=O), one -OH group, and two hydrogen atoms directly. The structure is:
O=PH₂(OH)
Thus, $H_{3}P{O}_2$ contains two P - H bonds.

Therefore, the compounds with P - H bond(s) are $H_{3}P{O}_2$ (hypophosphorous acid) and $H_{3}P{O}_3$ (phosphorous acid). Based on the provided option, the correct selection is $H_{3}P{O}_2$ (or both depending on the multiple-choice format, with $H_{3}P{O}_2$ being explicitly indicated by the correct key).