In which of the following collections is the Input/Output index-based?

1. Stack
2. Queue
3. BitArray
4. ArrayList
5. HashTable

class Sample
{
    int len;
    public int Length
    {
        get
        {
            return len;
        } 
    } 
}

class Sample
{
    public int Length
    {
        get
        {
            return Length;
        } 
    } 
}

class Sample
{
    int len;
    public int Length
    {
        get
        {
            return len;
        } 
        set
        {
            len = value;
        } 
    } 
}

class Sample
{
    int len;
    public int Length
    {
        Readonly get
        {
            return len;
        } 
    } 
}

1. The overridden base method must be virtual, abstract or override.
2. Both the override method and the virtual method must have the same access level modifier.
3. An override declaration can change the accessibility of the virtual method.
4. An abstract inherited property cannot be overridden in a derived class.
5. An abstract method is implicitly a virtual method.

1. if(s1 = s2)

2. if(s1 == s2)

3. int c;
   c = s1.CompareTo(s2);

4. if( strcmp(s1, s2) )

5. if (s1 is s2)

1. If our program does not catch an exception then the .NET CLR catches it.
2. It is possible to create user-defined exceptions.
3. All types of exceptions can be caught using the Exception class.
4. CLRExceptions is the base class for all exception classes.
5. For every try block there must be a corresponding finally block.

    int[] intMyArr = {11, 3, 5, 9, 4}; 

1. this reference can be modified in the instance member function of a class.
2. Static functions of a class never receive the this reference.
3. Instance member functions of a class always receive a this reference.
4. this reference continues to exist even after control returns from an instance member function.
5. While calling an instance member function we are not required to pass the this reference explicitly.