Q.Given the following class Test and assuming all necessary header file(s) included, answer the questions that follow the code: class Test { int Marks; char TName[20]; public: Test(int M) //Function 1 { Marks = M; } Test(char S[]) //Function 2 { strcpy(TName,S); } Test(char S[], int M) //Function 3 { Marks = M; strcpy(TName,S); } Test(Test &T) //Function 4 { Marks = T.Marks + 10; strcpy(TName,T.TName); } }; void main() { Test T1(10); //Statement I Test T2(70); //Statement II Test T3(30, "PRACTICAL"); //Statement III _______________; //Statement IV }

Concept: Constructor overloading and copy constructor.

(i) Statement III is incorrect. The constructor Test(char S[], int M) expects the string first and the integer second, but the call Test T3(30, "PRACTICAL") passes an integer first and a string second — no matching constructor exists. Statements I and II are correct.

(ii) Function 4 is the copy constructor. It initializes a new object using an existing object of the same class. …

Let's understand the problem step by step.

The class Test has two data members: an integer Marks and a character array TName of size 20. It defines four constructors — each is a different overloaded version.

1. Understanding each constructor

Function 1: Test(int M) — takes a single integer. It sets Marks = M but leaves TName uninitialized (garbage).

Function 2: Test(char S[]) — takes a single C-string. It copies the string into TName but leaves Marks uninitialized.

Function 3: Test(char S[], int M) — takes a C-string first, then an integer. It sets both members.

Function 4: Test(Test &T) — takes a reference to another Test object. It copies TName from T, but sets Marks = T.Marks + 10 (not a direct copy). This is a copy constructor because it takes a reference to the same class type.

2. Checking each statement in main()

Statement I: Test T1(10);

This matches Function 1 (single integer). Correct.

Statement II: Test T2(70);

Again matches Function 1. Correct.

Statement III: Test T3(30, "PRACTICAL");

Here the first argument is an integer 30, and the second is a string "PRACTICAL". But Function 3 expects (char[], int) — string first, integer second. So the order is reversed.

C++ will try to match:

• Function 3 expects (char[], int) — doesn't match because 30 is not a string.
• No other constructor takes two arguments. So this statement is incorrect.

Statement IV: It's blank — we need to fill it so that Function 4 (the copy constructor) executes.

3. What is Function 4?

Function 4 is Test(Test &T) — a constructor that takes a reference to an existing object of the same class. This is the copy constructor. …