How to Join and Filter Two Table through LINQ Query with C#

using System;
using System.Linq;
namespace CSharpLINQ
{
    class SimpleQuery
    {
        static void Main()
        {
            var students = new [] // Array of objects of an anonymous type
                {
                    new
                    {
                        ID = "101", LName = "Mishra", FName = "Kuldeep", Age = 31, ClassID = "101"
                    },
                    new
                    {
                        ID = "102", LName = "Sharma", FName = "Ramesh", Age = 20, ClassID = "101"
                    },
                    new
                    {
                        ID = "103", LName = "Sharma", FName = "Manoj", Age = 21, ClassID = "101"
                    },
                    new
                    {
                        ID = "104", LName = "Mishra", FName = "Rajesh", Age = 45, ClassID = "101"
                    },
                    new
                    {
                        ID = "105", LName = "Soni", FName = "Suresh", Age = 35, ClassID = "102"
                    },
                    new
                    {
                        ID = "106", LName = "Goyal", FName = "Dinesh", Age = 15, ClassID = "102"
                    },
                    new
                    {
                        ID = "107", LName = "Mishra", FName = "Jignesh", Age = 31, ClassID = "103"
                    },
                    new
                    {
                        ID = "108", LName = "Sharma", FName = "Mrigesh", Age = 20, ClassID = "103"
                    },
                    new
                    {
                        ID = "109", LName = "Verma", FName = "Prakash", Age = 21, ClassID = "103"
                    },
                    new
                    {
                        ID = "110", LName = "Mishra", FName = "Aakash", Age = 45, ClassID = "103"
                    },
                    new
                    {
                        ID = "111", LName = "Soni", FName = "Dinkar", Age = 35, ClassID = "102"
                    },
                    new
                    {
                        ID = "112", LName = "Goyal", FName = "Divakar", Age = 15, ClassID = "103"
                    },
                    new
                    {
                        ID = "113", LName = "Goyal", FName = "Bhaskar", Age = 31, ClassID = "103"
                    },
                    new
                    {
                        ID = "114", LName = "Sharma", FName = "Tanuj", Age = 20, ClassID = "104"
                    },
                    new
                    {
                        ID = "115", LName = "Verma", FName = "Anuj", Age = 21, ClassID = "104"
                    },
                    new
                    {
                        ID = "116", LName = "Goyal", FName = "Dhanush", Age = 45, ClassID = "105"
                    },
                    new
                    {
                        ID = "117", LName = "Soni", FName = "Mulri", Age = 35, ClassID = "105"
                    },
                    new
                    {
                        ID = "118", LName = "Goyal", FName = "Manohar", Age = 15, ClassID = "105"
                    },
                    new
                    {
                        ID = "119", LName = "Mishra", FName = "Sohan", Age = 31, ClassID = "105"
                    },
                    new
                    {
                        ID = "120", LName = "Sharma", FName = "Ram", Age = 20, ClassID = "101"
                    },
                    new
                    {
                        ID = "121", LName = "Soni", FName = "Mohan", Age = 21, ClassID = "106"
                    },
                    new
                    {
                        ID = "122", LName = "Soni", FName = "Rohan", Age = 45, ClassID = "106"
                    },
                    new
                    {
                        ID = "123", LName = "Soni", FName = "Rahul", Age = 35, ClassID = "101"
                    },
                    new
                    {
                        ID = "124", LName = "Goyal", FName = "Rohit", Age = 15, ClassID = "106"
                    }
                };
            var Class = new []
            {
                new
                {
                    ClassID = "101", Class = "I"
                },
                new
                {
                    ClassID = "102", Class = "II"
                },
                new
                {
                    ClassID = "103", Class = "III"
                },
                new
                {
                    ClassID = "104", Class = "IV"
                },
                new
                {
                    ClassID = "105", Class = "V"
                },
                new
                {
                    ClassID = "106", Class = "VI"
                },
            };
            var query = from student in students join cls in Class on student.ClassID equals cls.ClassID where student.ClassID == "103"
            select student;
            Console.WriteLine("Only Students of Class \"III\":");
            foreach(var q in query)
            {
                Console.WriteLine(" {0}, Age: {1}", q.FName, q.Age);
            }
        }
    }
}