What is a good substitute for an if else if in ComboBox in C#?

I need to develop a Employee Payroll Computation for my exam. enter image description here

I have successfully entered a code for when the Employee Number is chosen, there is a list of 1,2,3,4,5 and every number, a name appears on the Employee Name. I would like to know if there is another way to code it?

if (cmbEmployeeNum.SelectedIndex == 0)
        {
            txtEmployeeName.Text = "Sheldon Cooper";                
        }
        
        else if (cmbEmployeeNum.SelectedIndex == 1)
        {
            txtEmployeeName.Text = "Leonard Hofstadter";
        }
        
        else if (cmbEmployeeNum.SelectedIndex == 2)
        {
            txtEmployeeName.Text = "Howard Wolowitz";
        }
        
        else if (cmbEmployeeNum.SelectedIndex == 3)
        {
            txtEmployeeName.Text = "Raj Koothrappali";
        }
        
        else
        {
            txtEmployeeName.Text = "Penny";
        }

Also, Position Code is also in ComboBox. Do I only use the same code style because in position code, there is A, B, C and every code has an equivalent rate per day.

My teacher gave this final exam to us but he didn't really teach us the other lessons.

Thanks in advance.