Final answer:
The correct form for covering buildings under construction is the Builders Risk. This insurance specifically addresses risks pertinent to the building process. Other forms cover varying aspects of business property.
Step-by-step explanation:
The coverage form designed to cover buildings under construction is D. Builders Risk. This type of insurance is specifically tailored to cover the unique risks associated with buildings during the course of construction, including materials, fixtures, and equipment used in the building process that are on site, in transit, or being stored at other locations. Other forms, such as A. Extra expense form, B. Business income form, and C. Building and personal property form, are designed to cover different aspects of business property, but not specifically focused on construction risks as the Builders Risk form is.