If $\text{P}$ denotes $+$, $\text{Q}$ denotes $-$, $\text{R}$ denotes $\times$, and $\text{S}$ denotes $÷$, which of the following statements is mathematically correct?

Let us check option D by substituting the respective mathematical operators and applying the BODMAS rule:
Given expression in option D:

$$8\text{ R }8\text{ P }8\text{ S }8\text{ Q }8$$

Substituting operators:

$$8\times 8+8÷8-8$$

Applying BODMAS rule:

1. **Division ($÷$):**

$$8÷8=1⟹8\times 8+1-8$$

2. **Multiplication ($\times$):**

$$8\times 8=64⟹64+1-8$$

3. **Addition ($+$):**

$$64+1=65⟹65-8$$

4. **Subtraction ($-$):**

$$65-8=57$$

Since $\text{LHS}=\text{RHS}=57$, statement D is perfectly correct.