Final answer:
The presence or absence of lead-based paint is the item on the Seller's Disclosure that is based on a federal disclosure law.
Step-by-step explanation:
The item on the Seller's Disclosure that is based on a federal disclosure law is the presence or absence of lead-based paint. Lead-based paint was banned by the U.S. government for use in housing in 1978, but many older homes still have this paint. The federal law requires sellers to disclose the presence of lead-based paint in a property to protect buyers from potential health hazards.