Вот пример:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data;
namespace ConsoleApplication1
{
class Program
{
const string FILENAME = @"c:\temp\test.xml";
static void Main(string[] args)
{
DataTable dt = new DataTable("Test_1");
dt.Columns.Add("Number", typeof(int));
dt.Columns.Add("Question", typeof(string));
dt.Columns.Add("Answer", typeof(string));
dt.Columns.Add("A", typeof(string));
dt.Columns.Add("B", typeof(string));
dt.Columns.Add("C", typeof(string));
dt.Columns.Add("D", typeof(string));
dt.Columns.Add("E", typeof(string));
dt.Rows.Add(new object[] { 1, "Red Fruit", "A", "Apple", "Banana", "Grape", "Orange", "Pear" });
dt.Rows.Add(new object[] { 2, "How much is 1 + 2", "C", "1", "2", "3", "4", "5" });
dt.WriteXml(FILENAME);
}
}
}