.NET Linq. Confusion about SelectMany
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In the given code example, why do we use x.ToArray() ?
Each element x is already an array isn't it ?

Please make me less confused :)


        var array1 = new int[3] { 1, 2, 3 };     //New integer array
        var array2 = new int[3] { 4, 5, 6 };     //New integer array
        var array3 = new int[3] { 7, 8, 9 };     //New integer array

        IList<int[]> list4 = new List<int[]> { array1, array2, array3 };

        var theManyList = list4.SelectMany(x => x.ToArray()).ToList();