Which subquery cannot be executed by itself as a separate statement?

Solution (By Examveda Team)

This question is about different types of subqueries in MySQL. Let's break it down:
Subqueries are queries within other queries. They are used to fetch data that is then used in the main query.
Correlated Subqueries depend on the outer query. They can't be executed alone because they need information from the main query to work. Think of them as helper queries that need a specific context.
Uncorrelated Subqueries are independent. They can be executed on their own because they don't rely on any external information.
EXISTS and NOT EXISTS subqueries check if certain data exists in a table. They can also be run independently.
So, the answer is Option A: Correlated
Correlated subqueries cannot be executed independently because they rely on data from the outer query. They are like little assistants that need the main query's instructions to work.