When he saw me coming up the officer said, 'We've lost that information, [dang] it! They've killed that Arab of yours.'

'We've lost it,' I said.

I went over to Abdul-Karim's body and turned it over. He looked as though he had seen me swimming in the pool a few moments ago. His was not the expression of a man who had lost.

There, in the courtyard, it was I, all of us, who were the losers.
After reading this, the reader can most likely conclude that the narrator is upset because
he knows Abdul-Karim was hiding secrets.
he realizes Abdul-Karim was never his friend.
he understands that Abdul-Karim did not fear death.
he regrets his involvement in the sudden turn of events.

he regrets his involvement in the sudden turn of events.

Based on the given information, the reader can most likely conclude that the narrator is upset because he regrets his involvement in the sudden turn of events. This can be inferred from the statement, "There, in the courtyard, it was I, all of us, who were the losers." This suggests that the narrator feels a sense of responsibility and guilt for what has happened, indicating regret.