Final answer:
According to the 2005 UNDP Human Development Report, child mortality (under age 5) has declined in all regions of the world except for Sub-Saharan Africa.
Step-by-step explanation:
According to the 2005 UNDP Human Development Report, child mortality under age 5 has declined in all regions of the world except for (b) Sub-Saharan Africa. The report indicates that South Asia, Middle East and North Africa, and other regions have experienced a decline in child mortality rates. However, Sub-Saharan Africa still struggles with high child mortality rates due to various factors, including poverty, malnutrition, lack of access to healthcare, and unsanitary living conditions.