“Oedipus Rex”: What does the word seer most closely mean as it is used in the following passage?

“Teiresias, seer who comprehendest all,
Lore of the wise and hidden mysteries,
High things of heaven and low things of the earth
Thou knowest, though thy blinded eyes see naught,
What plague infects our city; and we turn
To thee, O seer, our one defense and shield.”
a)

a person with 20/20 vision

b)

a person who is well-traveled and has seen most of the world

c)

a person who is psychic and can foretell the future

d)

the night watchman at the city gates