Step 1: Let’s understand the meanings of the given options:
- A Thief is a person who steals property, usually without confrontation.
- A Burglar is someone who illegally enters a building, often to commit theft.
- The word Nandal is not a standard English term; it may be a distractor.
- An Intruder is anyone who enters a place without permission or invitation, regardless of whether theft or harm is intended.
Step 2: The question does not specify theft, only entry without invitation. This matches the general meaning of “Intruder.”
Step 3: Therefore, the correct choice is $\mathbfIntruder$.