You can add as many elseif levels as you like, and optionally at the end, you could add a catch-all else block:
if (returnedLevel == 1)
{
Response.Redirect("CEOPage.aspx");
}
else if (returnedLevel == 2)
{
Response.Redirect("IALOPage.aspx");
}
else if (returnedLevel == 3)
{
Response.Redirect("SomeOtherPage.aspx");
}
else
{
Response.Redirect("SomeDefaultPage.aspx");
}
And as jkirkerx suggested in the comments, a switch/Case statement would work as well.