In Cannizzaro reaction given below :
` 2PhCHO overset(: OH^(-)) to PhCH_(2)OH + PhCOO^(-)` the slowest step is

Options

A. The attack of `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`

Explanation

In the Cannizzarro's reaction given below `:`
`2Ph-CHO overset( OH^(-))(rarr) Ph -CH_(2)OH +PhCOO^(-)`
The slowest step is transfer of hydride oin ( refer to the mechanism of Cannizzaro reaction ) to the carbonyl group of second mole of aldehyde . Hence, it is represented in following reaction mechanism.