Assertion (A): Keys of the dictionaries must be unique.

Reasoning (R): The keys of a dictionary can be accessed using values.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Assertion (A): clear() method removes all elements from the dictionary.

Reasoning (R): len() function cannot be used to find the length of a dictionary.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

What are the similarities and differences between tuples and lists?

What is a key-value pair in dictionary?