(PUC - RJ 2001 - adaptada)
The Nun Study: Unlocking the Secrets of Alzheimer's
[...]
Much of this knowledge comes from a single, powerful piece of ongoing research: the aptly named Nun Study. Since 1986, University of Kentucky scientist David Snowdon has been studying 678 School Sisters- painstakingly researching their personal and medical histories, testing them for cognitive function and even dissecting their brains after death. Over the years, as he explains in Aging with Grace, a moving, intensely personal account of his research, Snowdon and his colleagues have teased out a series of intriguing-and quite revealing-links between lifestyle and Alzheimer's.
Adapted from Time, May 14, 2001
The word 'them', in the phrase 'testing them for cognitive function' (in bold), refers to:
David Snowdon and his colleagues.
The Nuns.
Snowdon's sisters.
Personal and medical histories.
678 teachers.