I have a drop down list which contains home and personal. 

As you will know, they will have different loan terms. For example when I click on home, I only want 20 and 25 to be shown. But when i click on personal loan, I am only able to choose from 5 or 10

sqlStr.AppendLine("SELECT LoanTerm, LoanRate From TDLoanRate ");
        sqlStr.AppendLine("where GETDATE() between LoanEffectFrom and LoanMaturity and ");

How do i filter this?