The correct order of reactivity of `PhMgBr` with:
(I) `Ph-overset(O)overset(||)(C)-Ph` (II) `CH_(3)-oversetoverset(O)(||)(C)-H`
(III) `CH_(3)-oversetoverset(O)(||)(C)-CH_(3)` is:

Options

A. `IgtIIgtIII`
B. `IIIgtIIgtI`
C. `IIgtIIIgtI`
D. `IgtIIIgtII`

Explanation

To determine the correct order of reactivity of `PhMgBr` with the given compounds, we need to analyze the electron deficiency of the carbonyl carbon in each compound. The reactivity of Grignard reagents like `PhMgBr` is influenced by the electron density at the carbonyl carbon, which affects how readily it can react with nucleophiles.

### Step-by-Step Solution:

1. **Identify the Compounds:**
- (I) `Ph-overset(O)overset(||)(C)-Ph` (Benzophenone)
- (II) `CH3-overset(O)(||)(C)-H` (Acetaldehyde)
- (III) `CH3-overset(O)(||)(C)-CH3` (Acetone)
...