Why must the base class be specified before interfaces when declaring a derived class?

Question

public interface ITest
{
    int ChildCount { get; set; }
}

public class Test
{
}

public class OrderPool : ITest, Test
{
    public int ChildCount
    {
        ge         


        

Answer 1

The order makes clear sense, the base class can implement members of the interface for the derived class, therefore the compiler must know of them beforehand