JQuery :: Get Multiple Form Input - Select Values From The Same Page In Php?

I have multiple <select></select> elements in a php page. After an option is chosen from the first drop down <select></select> element, options of the 2nd drop down <select></select> element will show up. Selection of an option from the 2nd drop down list will get the options in the 3rd dropdown list show up. Thus input from the 3rd drop down list will show up the options in the 4th drop down list. Such is the case for the 4th, 5th ,... drop down list.

Each time depending on the inputs from the previous drop down lists , the values for the immediately later drop down list will be retrieved from the database. i.e options for the nth drop down list to be retrieved from the database will depend on the selected the values from 1st, 2nd, 3rd, .....(n-1)th drop down list.