With no explanation, label text_A→text_B with either "DON'T KNOW", "NO" or "YES".
text_A: Flavius Claudius Julianus was born at Constantinople in 331, the son of Julius Constantius, consul in 335 and half-brother of the emperor Constantine, by his second wife, Basilina, a woman of Greek origin. Both of his parents were Christians. Julian's paternal grandparents were the emperor Constantius Chlorus and his second wife, Flavia Maximiana Theodora. His maternal grandfather was Julius Julianus, Praetorian Prefect of the East under the emperor Licinius from 315 to 324, and consul "suffectus" in 325. The name of Julian's maternal grandmother was lost during his lifetime, and was unknown to historians until fairly recently.
text_B: If Flavius Claudius Julianus himself had assembled his own family tree late in his life, would the line showing his four grandparents match that which a present-day historian could put together using the best-available information?
NO.