Which declaration doesn't use the same number of bytes and consumption of bytes depends on the input data?

This question is about how much storage space different data types in MySQL use. Let's break down the options:
Option A: Varchar
Varchar is a variable-length character string data type. This means it uses only as much space as it needs to store the actual data you put in.
Example: If you store "hello" in a Varchar column, it will use only 5 bytes.
Option B: Char
Char is a fixed-length character string data type. It always uses a set amount of space, even if you don't fill it completely.
Example: If you define a Char column with a length of 10, it will use 10 bytes, whether you store "hello" (5 bytes) or "goodbye" (7 bytes) in it.
Option C: Both Varchar and Char
This is the correct answer. Varchar uses variable space based on the data, while Char uses fixed space based on the defined length.
Option D: None of the mentioned
This is incorrect because both Varchar and Char have different storage behaviors.
In summary:
Varchar is flexible and uses less space for shorter data, while Char is predictable and uses fixed space, even if it's not fully used.
Therefore, the correct answer is Option C: Both Varchar and Char.