这是一道GRE逻辑题 Neither the Sami nor the Kephrian delegationsatte

这是一道GRE逻辑题
Neither the Sami nor the Kephrian delegations
attended the international conference.Beforehand.the
delegations of Daqua and Kephria.allies whose
governments had grievances against Tessia.officially
announced that one or both of the two would stay away
if the Tessian delegation attended the conference.In
response,the Sami delegation officially announced that
it would definitely attend if both the Daquan and
Kephrian delegations stayed away.
If the statements given are all true and all the
delegations adhered to their official announcements.
it must also be true that the
(A) Daquan delegation attended the conference
(B) Daquan delegation did not attend the conference
(C) Sami government had no grievance against
Tessia
(D) Tessian delegation did not attend the conference
(E) Tessian delegation made no official
announcement regarding its attendance at the
conference