In 1978, the federal government banned the use of ______ in housing.

The correct response is the ban on the use of lead-based paint in housing, which occurred in 1978. This significant legislation was introduced due to the harmful health effects associated with lead exposure, particularly in young children. Lead-based paint was commonly used in homes built before the ban, and it posed serious risks of lead poisoning, which can lead to developmental issues, neurological impairment, and other health problems.

The decision to ban lead-based paint was a part of broader efforts to protect public health and ensure safer living environments, especially for vulnerable populations. As a result, the federal government emphasized the importance of addressing lead hazards in homes and mandated disclosure of lead paint presence in real estate transactions involving homes built before 1978.

Other options provided in the question do not represent legislation enacted in 1978 regarding housing materials and safety. Asbestos, for instance, was subject to regulation, but not an outright ban in that specific year. Glue-backed wallpaper does not have significant health implications that led to federal legislation, and spiral staircases are addressed in building codes for safety but are not banned. Thus, the focus on lead-based paint sets a clear historical context for the regulatory actions taken by the federal government to safeguard public health in residential settings.