C# inherit

Case：class A has a construct. class B is inherit from class A and B also has a construct. What's the order of the construct execute?

Result: construct A -> construct B.

Sample:

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

namespace TestInheritConstruct
{
    public class Program
    {
        public static void Main(string[] args)
        {
            B b = new B();
            Console.ReadLine();
        }
    }

    public class A
    {
        public A()
        {
            Console.WriteLine("Construct A.");
        }
    }

    public class B : A
    {
        public B()
        {
            Console.WriteLine("Construct B.");
        }
    }
}