Day 9 Night: Python Programming – Functions & Scope (with 10 MCQs)

Let’s master how functions work in Python – from defining custom logic to understanding variable scope and returning values. This is a must-know topic for logic building and coding rounds.

Concept Notes: Python Functions & Scope

🔹 1. What is a Function?

A function is a block of code that performs a specific task and can be reused.

def greet():
    print("Hello!")

def greet():
    print("Hello!")

Use def to define a function.

🔹 2. Function With Parameters

def add(a, b):
    return a + b

def add(a, b):
    return a + b

• a and b are parameters
• return gives output

🔹 3. Calling a Function

result = add(5, 3)
print(result)  # Output: 8

result = add(5, 3)
print(result)  # Output: 8

🔹 4. Types of Arguments

• Positional: Based on order
• Keyword: Named explicitly
• Default: Value given during definition
• Variable-length: *args and **kwargs

🔹 5. Scope of Variables

x = 10  # Global

def func():
    x = 5  # Local
    print(x)  # 5

x = 10  # Global

def func():
    x = 5  # Local
    print(x)  # 5

🔹 6. Global Keyword

x = 10

def modify():
    global x
    x = 20

x = 10

def modify():
    global x
    x = 20

Allows modifying a global variable inside a function.

🔹 7. Return vs Print

• return gives value to caller
• print only displays output

def square(x):
    return x*x

def square(x):
    return x*x

🔹 8. Recursive Function

A function that calls itself:

def fact(n):
    if n == 0:
        return 1
    return n * fact(n - 1)

def fact(n):
    if n == 0:
        return 1
    return n * fact(n - 1)

op 10 MCQs – Functions & Scope in Python

1️⃣ Which keyword is used to define a function in Python?
A) function
B) def
C) define
D) func

2️⃣ What does the return statement do?
A) Ends the program
B) Exits the loop
C) Returns value from a function
D) Prints the result

3️⃣ What is the output of:

def add(x, y):  
    return x + y  
print(add(3, 4))

def add(x, y):  
    return x + y  
print(add(3, 4))

A) 7
B) 34
C) add
D) Error

4️⃣ What is the default return value of a function without a return statement?
A) 0
B) undefined
C) None
D) Error

5️⃣ Which of these are valid variable scopes?
A) Local
B) Global
C) Both
D) None

6️⃣ What will be the output?

x = 5  
def show():  
    x = 10  
    print(x)  
show()

x = 5  
def show():  
    x = 10  
    print(x)  
show()

A) 5
B) 10
C) Error
D) None

7️⃣ To modify a global variable inside a function, use:
A) static
B) extern
C) global
D) public

8️⃣ What is printed here?

def test(a=3, b=4):  
    print(a * b)  
test(2)

def test(a=3, b=4):  
    print(a * b)  
test(2)

A) 8
B) 6
C) 12
D) Error

9️⃣ Choose the correct recursive function:
A) def r(): r()
B) def r(): print(r)
C) def r(): return r()
D) Both A & C

🔟 What is the difference between print and return?

A) return gives value, print displays
B) return prints value
C) print stores value
D) Both are same

✅ Answer Key

📖 Explanations

• Q1: Python uses def to define functions.
• Q2: return sends back result from the function.
• Q3: 3 + 4 = 7.
• Q4: If no return – function returns None.
• Q5: Local and Global are two main scopes.
• Q6: Local x = 10, so output is 10.
• Q7: Use global to access/modify a global variable.
• Q8: b defaults to 4 → 2 × 4 = 8.
• Q9: A and C are recursive (they call themselves).
• Q10: return passes values, print only shows.

📥 Download Notes + MCQs PDF

👉 Get PDF from: @learnnewthingsoffcial

💬 Comment Task

💬 Share one Python function you wrote recently in the group and we’ll give feedback 💻🔥