Correct Answer:
B. As
The correct answer is As because this creates a grammatically correct equative comparison mapping an identical degree of certainty between two subjects.
- As: This is the correct choice. In English grammar, the comparative structure 'as + adjective + as' is a fixed construction used to declare that two entities possess a characteristic to an equal extent.
- Incorrect Options:
- Quite / Very: These are incorrect. While they function as regular intensifiers (e.g., 'I am very sure'), inserting them here results in an incomplete and broken comparative structure when paired with the trailing 'as you are'.