Identify the (X), (Y), and (Z) in the following reactions
`PhCH_(2)Br+CH_(3)-overset(O)overset(||)(C)-CH_(3)underset("(ii) :"B^(Theta))overset("(i) "Ph_(3)P)rarr(X)`

Explanation

To solve the problem, we need to identify the compounds (X), (Y), and (Z) in the given reactions involving phenyl bromide (PhCH₂Br), acetone (CH₃C(=O)CH₃), and the reagents triphenylphosphine (Ph₃P) and a base.

### Step-by-Step Solution:

1. **Identify the Reactants:**
- The first reactant is phenyl bromide (PhCH₂Br), which contains a phenyl group (Ph) attached to a bromomethyl group (CH₂Br).
- The second reactant is acetone (CH₃C(=O)CH₃), which is a ketone.

...