Given a context passage, generate a question from the passage such that its answer is shortest continous span from the passage.

[Q]: P&O European Ferries (formerly Townsend Thoresen), a division of P&O Ferries, was a ferry company which operated in the English Channel from 1987 after the Herald of Free Enterprise disaster, when Townsend Thoresen was renamed P&O European Ferries, until 1999 when the Portsmouth Operations became P&O Portsmouth and the Dover Operation where merged with Stena Line AB to make P&O Stena Line.
[A]: What is the ending year of P&O European Ferries?


[Q]: Decameron Nights is a 1953 anthology Technicolor film based on three tales from The Decameron by Giovanni Boccaccio, specifically the ninth and tenth tales of the second day and the ninth tale of the third.
[A]: The Decameron Nights is based upon what?


[Q]: SET domain genes have been identified in numbers of bacterial genomes based on similarity to SET domains of eukaryotic histone methyltransferases. Herein, a Chlamydophila pneumoniae SET domain gene was clarified to be coincidently expressed with hctA and hctB genes encoding chlamydial histone H1-like proteins, Hc1 and Hc2, respectively. The SET domain protein (cpnSET) is localized in chlamydial cells and interacts with Hc1 and Hc2 through the C-terminal SET domain. As expected from conservation of catalytic sites in cpnSET, it functions as a protein methyltransferase to murine histone H3 and Hc1. However, little is known about protein methylation in the molecular pathogenesis of chlamydial infection. cpnSET may play an important role in chlamydial cell maturation due to modification of chlamydial histone H1-like proteins.
[A]:
What is the characteristic domain of histone methyltransferases?