In an Instagram post on Wednesday, Tottenham Hotspur's Son said he will be available for selection at the World Cup after undergoing surgery to stabilise a fracture around his left eye.
He added that he would play with a protective mask if required.
Son sustained the injury in Tottenham's 2-1 Champions League tie at Olympique de Marseille last week.
"Of course, he's going to be selected," Bento told reporters, adding that there was no 'Plan B'.
"It's a situation that's going to demand certain things and adaptations. We should let him come and do what he should do. And after that, we have time to make the right decision and best decisions for all of us.
"For us, it's something normal from Sonny. We already had other moments where he was injured and he wanted to play. So it's not a surprise at all for us."
South Korea's hopes at the World Cup, which begins on November 20th, rest heavily on captain Son, who has scored 35 goals in 104 appearances for his country.
They kick off their campaign on November 24th against Uruguay and also face Ghana and Portugal in Group H.
