using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text.RegularExpressions;
 
public class Test
{
	public static void Main()
	{
		var s = ">>1<< First Option For Third Variable Reply1 >>1<<\n\n>>2<< Second Option For Third Variable Reply 1 >>2<<\n\n>>3<< Third Option For Third Variable Reply 1 \n>>3<<";
		var rx = @"(?<=>>([0-9]+)<<).*?(?=>>\1<<)";
		var results = Regex.Matches(s, rx, RegexOptions.Singleline)
					.Cast<Match>()
					.Select(m => m.Value);
		Console.WriteLine(string.Join("\n", results));
	}
}

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