Why benzaldehyde shows negative result in Tollen's test?

In fact Benzaldehyde can reduce Tollen's reagent (s-IL Finer) but nor Fehling's soln Or Benedict's soln.
This is becuse of lower reactivity of aromatic aldehydes.
In contrast to alkyl group in aliphatic aldehyde ,aryl group in aromatic aldehyde shows -I effect, So in case of Aliphatic aldehyde (because of the +I effect of alkyl group) electron density in carbonyl group becomes high & so they can easily loose electrons & get oxidised.
But in case of Benzaldehyde -I effect of aryl group decreases the electron density in carbonyl group causing it to be less susceptible to electron loss & hence oxidation.
So mild oxidising agents like Fehling's soln can't oxidise benzaldehyde.