how to show a first item in a combobox in c# winforms

Code Example 1

comboBox1.SelectedItem = "your value"; //

Code Example 2

var item = ChunkList.SingleOrDefault(x => x.UniqueId == ChunkID);
if (item != null)
    ChunkList.Remove(item);

Code Example 3

myList.Where(sublist => sublist.Any(item => item.Name == "ABC" && item.Action == "123"));