Which of the following statements is correct?

1. Data members ofa class are by default public.
2. Data members of a class are by default private.
3. Member functions of a class are by default public.
4. A private function of a class can access a public function within the same class.
5. Member function of a class are by default private.

namespace CuriousTabConsoleApplication
{ 
    class Sample
    { 
        public int index; 
        public int[] arr = new int[10]; 
        
        public void fun(int i, int val)
        { 
            arr[i] = val;
        }
    }
     
    class MyProgram
    { 
        static void Main(string[] args)
        {
            Sample s = new Sample(); 
            s.index = 20; 
            Sample.fun(1, 5); 
            s.fun(1, 5); 
        } 
    } 
}

int d; 
d = Convert.ToInt32( !(30 < 20) );

byte b1 = 0xAB;
byte b2 = 0x99;
byte temp;
temp = (byte)~b2;
Console.Write(temp + " ");
temp = (byte)(b1 << b2);
Console.Write (temp + " ");
temp = (byte) (b2 >> 2);
Console.WriteLine(temp);

1. The & operator can be used to Invert a bit.
2. The & operator can be used to put ON a bit.
3. The & operator can be used to put OFF a bit.
4. The & operator can be used to check whether a bit is ON.
5. The & operator can be used to check whether a bit is OFF.

int i;
int j = new int();
i = 10;
j = 20; 
String str; 
str = i.ToString(); 
str = j.ToString();

namespace CuriousTabConsoleApplication
{ 
    class Sample
    { 
        int i, j; 
        public void SetData(int ii, int jj)
        {
            this.i = ii;
            this.j = jj 
        } 
    } 
    class MyProgram
    { 
        static void Main(string[ ] args)
        { 
            Sample s1 = new Sample(); 
            s1.SetData(10, 2); 
            Sample s2 = new Sample(); 
            s2.SetData(5, 10); 
        } 
    } 
}

1. Sample s = new Sample();
2. Sample s;
3. Sample s; s = new Sample();
4. s = new Sample();

class Sample
{
    private int i;
    public Single j;
    private void DisplayData()
    {
        Console.WriteLine(i + " " + j);
    }
    public void ShowData()
    {
        Console.WriteLine(i + " " + j);
    }
}