What type of housing was specifically developed as walk-up units?

The correct choice pertains to Bagong Lipunan Sites and Services, which was particularly designed to provide affordable housing options through the development of walk-up units. This housing model aimed to address the urban housing crisis in the Philippines by offering accessible and cost-effective living solutions.

The walk-up unit format involves low-rise buildings without elevators, allowing residents to access their homes via stairs. This design not only promotes a sense of community by encouraging social interaction among residents but also aligns well with the economic conditions of many families who required practical and budget-friendly housing options.

Other listed options, while they may represent significant developments in urban planning or housing, do not specifically emphasize the walk-up unit model in the same manner. Bonifacio Global City and Filinvest Corporate City are known for their integrated urban environments that include various types of mixed-use developments but do not focus exclusively on walk-up housing. Philamlife Homes, on the other hand, represents a different housing approach that typically includes lower-density subdivisions rather than the specific walk-up design associated with Bagong Lipunan Sites and Services.