Texts: A person over 65 years old is experiencing age-related memory decline. A healthcare provider recommends brain training programs based on research indicating that dimensions of cognitive decline are partially reversible because the brain retains a functioning capacity to reorganize cortical tissue. This healthcare provider's recommendation is aligned with which of Baltes' key principles of lifespan development?
Development has gains and losses
Development has socio-cultural influences
Development is plastic
Development halts in old age