小兰上的一道题目

A medieval manuscript called L contains all eighteen extant tragedies
by the Greek playwright Euripides. Of these, ten called the “select
plays,” are accompanied in L by ancient commentaries and also
appear in other medieval manuscripts; this group includes some of
Euripides’ best-known works, including the Medea. The other eight,
which appear in alphabetical order, without commentary. The Electra is
one of the alphabeticals.

Which of the following can be reliably concluded on the basis of the
Statements given?

A. Only Euripides’ best-known works are accompanied by ancient
commentaries in extant medieval manuscripts.

B. The select plays are accompanied by ancient commentaries
because they were the best known of Euripides’ works.

C. No commentaries were written about Euripides’ Electra in
ancient times.

D. Euripides’ Medea never appears in medieval manuscripts
unaccompanied by ancient commentary.

E. Euripides’ Electra does not appear accompanied by a commentary
in any extant medieval manuscript.

答案E，为什么？

C为什么不对？

我一开始也是选E的，后来想通了

条件中tragedies分为两类，一类以M为代表，另一类以E为代表。那么E就是M的特征取反

M是accompanied in L by ancient commentaries and also appear in other medieval manuscripts

所以E是not appear accompanied by a commentary in any extant medieval manuscript

谢谢！