organic chemistry - Relative acidity of p-chlorobenzoic acid and p-flurobenzoic acid

I want to compare the relative acidity of p-chlorobenzoic acid and p-flurobenzoic acid. Both of the facts below point to p-chlorobenzoic acid being more acidic:

1. 
   
   

   The carboxylic acid group is too far away from the halogen for inductive effect to have any significance. The +M effect of fluorine is greater than chlorine (due to more effective orbital overlap). +M effect is not distance dependant and hence p-fluoroobenzoic acid should be less acidic since the negative charge on its conjugate base is destabilized.

   
   


2. 
   

   There is resonance of the negative charge of the carboxylate ion with the empty d-orbitals of chlorine which would stabilize it.

   
   

However, in reality, p-chlorobenzoic acid is less acidic than p-fluorobenzoic acid . Why?

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  $\mathrm{p}K_\mathrm{a}$ of para chlorobenzoic acid $\ce{-> 4.03}$.Source

  
  


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  $\mathrm{p}K_\mathrm{a}$ of para fluorobenzoic acid $\ce{-> 4.14}$.Source