C# - store multiple strings to list using while loop [duplicate]

I'm building a menu where the user can add multiple strings to "the backpack", using a while loop.

Tried to store addedItem to backpackContent so that the user can add multiple strings to backpackContentny [selecting "1"] multiple times. But when trying to print the backpack content [selection "2"] it doesn't print the strings we've added, but prints this:

The backpack contains: System.Collections.Generic.List`1[System.String]

Here's my code:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace backpack_stackoverflow
{
    internal class Program
    {
        static void Main(string[] args)
        {        

                bool controllBool = true;

                List<string> backpackContent = new List<string>();

                while (controllBool)
                {
                    Console.WriteLine("Welcome to the backpack.");
                    Console.WriteLine("[1] Add an item to backpack");
                    Console.WriteLine("[2] Print backpack content");
                    Console.WriteLine("[3] Clear backpack content");
                    Console.WriteLine("[4] Exit");

                    string menuSelection = Console.ReadLine();


                    switch (menuSelection)
                    {
                        case "1":
                            Console.WriteLine("Add something to the backpack: ");
                            string addedItem = Console.ReadLine();
                            backpackContent.Add(addedItem);
                            Console.WriteLine("You have added a " + addedItem + " to the backpack!");
                            break;

                        case "2":
                            if (menuSelection == "")
                            {
                                Console.WriteLine("The backpack is empty. Add something by pressing menu selection 1.");
                            }
                            else
                            {                                
                                Console.WriteLine("The backpack contains: " + backpackContent + ".");                            }
                            break;

                        case "3":
                            Console.WriteLine("You have cleared the backpack! Add something by pressing menu selection 1.");
                            break;

                        case "4":
                            controllBool = false;
                            break;


                        default:
                            Console.WriteLine("It seems you have made an invalid selection. Please make an selection between 1-4.");

                            break;

                   }

                }

            }
        }
    }