set values for 2nd selectbox from the selection of 1st selecbox

I have 2 select box as below. i want to make

1. when user select A on 1st select box: only the value 100, 300 will appear on the 2nd select box


2. when user select B on 1st select box: only the value 300, 900 will appear on the 2nd select box


3. when user select C on 1st select box: only the value 100, 600, 900 will appear on the 2nd select box



4. when user select D on 1st select box: only the value 100, 300, 900 will appear on the 2nd select box

   
   
   

   
   Select 1st
   A
   B
   C
   D
   
   
   Select 2nd
   100
   300
   600
   900
   

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