How to remove & from string using C# in ASP.Net

Use HttpUtility.HtmlDecode(stringvalue) to get the proper value like below.

HttpUtility.HtmlDecode("B.A.  IST YEAR") //Gives B.A.  IST YEAR
HttpUtility.HtmlDecode("B.A & Journalism") // Gives B.A & Journalism

Refer the below code.

// Get DataTable from database.
DataTable dt = new DataTable();
dt.Columns.AddRange(new DataColumn[] { new DataColumn("CourseId", typeof(int)), new DataColumn("CourseName", typeof(string)) });
dt.Rows.Add(1, "B.A. IST YEAR");
dt.Rows.Add(2, "B.A.(MassCommunication&Journalism)FinalYear");
dt.Rows.Add(3, "B.A.(MassCommunication&Journalism)IYear");
dt.Rows.Add(4, "B.A.(MassCommunication&Journalism)IIYear");
dt.Rows.Add(4, "B.A.(MassCommunication&Journalism)IIIYear");
if (dt.Rows.Count > 0)
{
    // Clone the dt.
    DataTable dt1 = dt.Clone();
    foreach (DataRow dr in dt.Rows)
    {
        // Add CourseId & CourseName to dt1 by removing & and  
        dt1.Rows.Add(dr["CourseId"], HttpUtility.HtmlDecode(dr["CourseName"].ToString()));
    }
    // Bind dt1 to dropdownlist
    ddlCourseName.DataSource = dt1;
    ddlCourseName.DataTextField = "CourseName";
    ddlCourseName.DataValueField = "CourseId";
    ddlCourseName.DataBind();
    ddlCourseName.Items.Insert(0, new ListItem("--Select--", "0"));
}