drop down list

in my page i hav two drop down list and a button.

1)i set the first drop down to sql data source and post back true such tht wen i select sumthing from tht other list will be filled automatically according to user selection.

2)then i select sumthing from 2nd drop down list and click on delete button, such tht a record is deleted with selected item in 2nd drop down list.

i am able to do the first one.

but wen i click delete button, my record is not deleted. it is not taking value of selected item in 2nd drop down list. plz provide me the code. i am doing a project on online exam system
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