In the Cannizzaro reaction given below:
`2Ph-CHO overset(overset(Θ)OH)rarrPh-CH_(2)OH+PhCO_(2)^(-)` the slowest step is:
A. The attack of `overset(Θ)(OH)` at the carbonyl group.
B. The transfer of hydride to the carbonyl group.
C. The abstraction of proton from the carboxylic acid.
D. The deprotonation of `Ph-CH_(2)OH`.
