using System;

using System.Linq;

using System.Collections.Generic;

using System.Text.Json;

public class Program

{

    public static string INPUT = @"{

    ""Results"": [{

            ""Components"": [{

                ""Attribute"": {

                    ""Values"": [{

                            ""Id"": ""1"",

                            ""MValue"": ""Physical""

                        },

                        {

                            ""Id"": ""2"",

                            ""MValue"": ""77777722060600""

                        },

                        {

                            ""Id"": ""3"",

                            ""MValue"": ""package""

                        }

                    ]

                }

​

            }]

        },

        {

            ""Components"": [{

                ""Attribute"": {

                    ""Values"": [{

                            ""Id"": ""1"",

                            ""MValue"": ""Non-Physical""

                        },                      

                        {

                            ""Id"": ""2"",

                            ""MValue"": ""77777745363707""

                        },                      

                        {

                            ""Id"": ""3"",

                            ""MValue"": ""355 ml""

                        }

                    ]

                }

​

            }]

        }

    ],

    ""ResultCount"": 2

}

";

    public static void Main()

    {

        var root = JsonSerializer.Deserialize<Rootobject>(INPUT);

        var result = root.Results

                         .SelectMany(x => x.Components)

                         .Select(x => x.Attribute)

                         .SelectMany(x => x.Values)

                         .Where(v => v.Id == "3")

                         .Select(v => v.MValue)

                         .ToList();

        Console.WriteLine($"[{(string.Join(", ", result))}]");

    }

}

​

public class Attribute

{

    public List<Value> Values { get; set; }

}

​

public class Component

{

    public Attribute Attribute { get; set; }

}

​

public class Result

{

    public List<Component> Components { get; set; }

}

​

public class Rootobject

{

    public List<Result> Results { get; set; }

    public int ResultCount { get; set; }

}

​

public class Value

{

    public string Id { get; set; }

    public string MValue { get; set; }

}