Given the question: I'm taking a test and have to guess the right answer to the question after the article. Article: We arranged that Kissinger would fly to Vietnam early in July and then stop in Pakistan on the way back. There he would develop a stomachache that would require him to stay in bed and not be seen by the press. Then, with President Yapha's help, he would be taken to the airport where a Pakistani jet would fly him over the mountains to China. Kissinger's trip was given the name Polo after Marco Polo, another Western traveler who made history by journey in China. Everything went quite smoothly. His slight illness in Islamabad received only small attention from reporters covering him. They accepted the story that he would be kept shut up for at least a few days and began making arrangements for their own activities. Because of the need for complete secrecy and the lack of any direct communication facilities between Beijing and Washington, I knew that we would have no word from Kissinger while he was in China. Even after he had returned to Pakistan, it would still be important to keep it secret, so before Kissinger left, we agreed on a single code word - Eureka - which he would use if his missions were successful and the presidential trip had been arranged. On July 11, Al Haig, who knew our code work, phoned to say that a cable from Kissinger had arrived. "What's the message?" I asked. "Eureka". he replied. Question: From the passage we can infer that Kissinger's cable carrying the message "Eureka" must have been sent _ . Options: A: before he had left Beijing B: soon after he had returned to Pakistan from China C: as soon as he had arrived in Washington on July 11 D: before he returned to Pakistan on July 11
The answer is:
B