
Answer: Severalty
Explanation: Severalty is a form of ownership of real estate in which the owner gets the exclusive right of the property. In other words, when a real estate property  is owned by a single individual or legal entity then such an ownership will be termed as ownership in severalty.
In the given case, TBH Â is the sole owner of the land adjacent to their headquarter.
Hence the form of ownership is severalty.