The correct answer is Option 2: 1 and 3 only.

UN-Habitat is the United Nations programme dedicated to promoting sustainable towns and cities that provide adequate shelter for all. The following points provide a detailed reasoning behind why options 1 and 3 are correct, while option 2 is incorrect:

1. UN-Habitat has been mandated by the United Nations General Assembly to promote socially and environmentally sustainable towns and cities to provide adequate shelter for all.

This statement is correct. The United Nations General Assembly has mandated UN-Habitat to promote socially and environmentally sustainable towns and cities to provide adequate shelter for all. UN-Habitat works towards achieving this goal by providing technical assistance, knowledge and capacity building, policy advice, and funding support to governments, local authorities, and other stakeholders.

For instance, UN-Habitat has been instrumental in promoting the implementation of the New Urban Agenda, which was adopted by the United Nations General Assembly in 2016. The New Urban Agenda is a global framework that guides the efforts of countries and cities towards achieving sustainable urban development.

2. Its partners are either governments or local urban authorities only.

This statement is incorrect. While governments and local urban authorities are important partners for UN-Habitat, they are not the only ones. UN-Habitat also collaborates with civil society organizations, private sector entities, academic institutions, and other stakeholders. This collaboration is essential to ensure that the policies and interventions promoted by UN-Habitat are relevant, effective, and inclusive.

For instance, UN-Habitat partners with grassroots organizations and community groups to support the development of slum upgrading projects. UN-Habitat also collaborates with the private sector to promote sustainable urbanization through initiatives such as the World Urban Campaign.

3. UN-Habitat contributes to the overall objective of the United Nations system to reduce poverty and to promote access to safe drinking water and basic sanitation.

This statement is correct. UN-Habitat`s work is closely aligned with the overall objective of the United Nations system to reduce poverty and to promote access to safe drinking water and basic sanitation. Urbanization can be a powerful driver of economic growth and poverty reduction, but it can also exacerbate inequalities and environmental degradation if not properly managed.

UN-Habitat works towards ensuring that urbanization is inclusive, sustainable, and resilient, with a particular focus on the needs of vulnerable and marginalized groups. For instance, UN-Habitat promotes the provision of basic services such as water, sanitation, and energy in informal settlements and slums, which are often neglected by public authorities.

In conclusion, UN-Habitat is an important United Nations programme that works towards promoting sustainable urbanization and providing adequate shelter for all. Its work is closely aligned with the overall objective of the United Nations system to reduce poverty and promote access to safe drinking water and basic sanitation. While governments and local urban authorities are important partners for UN-Habitat, the programme also collaborates with other stakeholders such as civil society organizations, private sector entities, and academic institutions.