Final Answer:
3) toilet because the term "lavatory" specifically refers to the toilet fixture in a bathroom.
Step-by-step explanation:
The term "lavatory" refers to the toilet in a bathroom. It's often used interchangeably with "toilet" to describe the fixture used for human waste disposal and sanitation purposes.
In bathroom terminologies, "lavatory" doesn't typically refer to a bathroom base cabinet, vanity, or sink but specifically denotes the toilet fixture itself.
The confusion might arise because "lavatory" can also refer broadly to a washing or cleansing area, encompassing the sink or basin where one washes their hands or face.
However, in the context of the question, considering the options provided and the specific terminology related to bathroom fixtures, "lavatory" directly correlates to the toilet.
Understanding bathroom terminology is essential for effective communication in plumbing or renovation discussions. Knowing the precise terms for each fixture helps in conveying specific requirements or issues accurately.
In this case, "lavatory" distinctly signifies the toilet, making it crucial to differentiate between various bathroom elements for efficient communication and understanding within the context of bathrooms and their varied sizes and components. Hence, therefore option 3) is correct.