How is Oedipus Rex a Greek tragedy?

Sophocles's immortal and mythical play, Oedipus
Rex is believed to be one of the best classical examples of tragedy.
Aristotle's theorizings in the Poetics were modelled on the tragedy
of Oedipus, the king of Thebes. The play is adjudged as a great example of tragic drama
on the basis of the following:

a) The play has a very
well-constructed plot that arouses the twin emotions of pity
and fear, and achieves the tragic
katharsis;

b) The play shows the
downfall of an exceptional human being belonging to high
rank/station;

c) The plot involves both
peripety(''reversal") and
anagnorisis("recognition") and, what is more, these two moments are
co-incidental;

d) The protagonist suffers because of a
tragic error or hamartia; he kills his father, Laius, and marries
his mother, Jocasta;

e) The protagonist's error is caused
by hubris, a form of pride that goes before a
fall.

Sophocles's play dramatizes the painful
mystery of pre-ordained suffering of an extra-ordinary human being, fate/circumstances
bringing about the downfall of an exemplary individual.