Custom scale printing in Adobe Acrobat

I have Acrobat X Pro and read

1. Choose File > Print.




2. Click Size, and choose one of the following options:

   
   
   
   
   • Fit Scales small pages up and large pages down to fit the paper.
   
   
   • Shrink Oversize Pages
   
   
   • Resizes only large pages to fit the paper, and prints small pages as they are.
   
   
   • Custom scale Resizes pages by the percentage you specify.
     Note: If you don’t see a Page Scaling options, click the arrow next to the Printer menu to expose more controls in the Print dialog box.
   
   

I do see all options except the latter. What is the arrow next to the Printer Menu? Why does Adobe pass the scaling buck to the printer, why custom scaling is hidden in my case?