Chomsky Hierarchy

Step 1: Understanding the Chomsky Hierarchy.
In the Chomsky hierarchy, languages are classified into four types based on their complexity: - Type 0: Recursively enumerable languages

- Type 1: Context-sensitive languages

- Type 2: Context-free languages

- Type 3: Regular languages

The hierarchy is ordered as follows, with each type being a subset of the next:

Step 2: Applying the Order.
From the Chomsky hierarchy, we know that regular languages ( ) are the simplest and are a subset of context-free languages ( ), which in turn are a subset of context-sensitive languages ( ), and finally, recursively enumerable languages ( ) are the most general.

Step 3: Conclusion.
Therefore, the correct order from subset to superset is , , , and , which corresponds to option (1) A, B, C, D.