Read the following passage and questions, then choose the right answer from options, the answer should be one of A, B, C, D.

<passage>:
RETIEF OF THE RED-TAPE MOUNTAIN Retief knew the importance of sealed at Vice-Consul Retief. "Still," Retief said, "it gives an opportunity to travel—" "Travel!" the consul barked. "I hate travel. Here in this backwater system particularly—" He paused, blinked at Retief and cleared his throat. "Not that a bit of travel isn't an excellent thing for a take certain action." He swung back to face Retief. "I'm sending you in to handle the situation, Retief—under sealed orders." He picked over the edge of the desert?" "I'm supposed to be preventing the war," said Retief. "It looks like I'm a little late." "Hold on," said Retief. "I've got to get down. They won't shoot at you." punching keys on the console. Retief reached out, caught his wrist. The pilot plunged against the restraint, swung a punch that Retief Retief crawled into the narrow cockpit of the skiff, glanced over the controls. The pilot ducked out of sight, came back, handed Retief a departing mail boat. Retief watched the tiny screen, hands on the manual controls. He was dropping rapidly: forty miles, thirty-nine.... A crimson blip showed on the screen, moving out. Retief felt sweat pop out on his forehead. The red blip meant heavy but by no means unheard of fission weapon. But maybe it was just on a high trajectory and had no connection with the skiff.... Retief altered course to the south. The blip followed. He checked instrument readings, gripped the controls, watching. This was going to be tricky. The missile bored closer. At five miles Retief threw the light skiff into maximum acceleration, straight toward the the missile, and Retief was slammed violently against the restraining Retief shook his head, kicked in the emergency retro-drive. Points Coughing, Retief disengaged himself from the shock-webbing. He beat Retief edged back around the trunk, eased down behind a fallen log. As he passed, Retief rose, leaped the log and tackled him. struggled in silence. Retief flipped him onto his back, raised a fist— move. Didn't know it was a Terrestrial. Who are you? What you doin' here? We're pretty close to the edge of the oases. That's Flap-jack country over there." He waved a hand toward the north, where the desert lay. "Missile, eh? Must be Flap-jack artillery. We got nothing like that." "I heard there was a full-fledged war brewing," said Retief. "I didn't expect—" "Keep your head down. These damn Flap-jacks have got some wicked hand weapons. Come on...." He moved off silently on all fours. Retief followed. They crossed two hundred yards of rough country before Potter Retief looked down at the charred, torn and sweat-soaked powder-blue Potter was on his way, loping off up a gentle slope. Retief pulled off Retief. "We put out the word back home. We all got relatives on Ivory "Lemuel!" Potter said. "Nobody else could sneak up on us like that." He eyed Retief. Retief got to his feet. "I think I should explain—" Lemuel stared at Retief. "You givin' me orders...?" Retief's left fist shot out, smacked Lemuel's face dead center. He dirt as he dropped it. He caught himself, jumped for Retief ... and met "No," said Retief. "You wait here. I'm going out alone." "Later. Sit tight and keep your eyes open." Retief took a bearing on a treetop faintly visible against the sky and started forward. Five minutes' stealthy progress brought him to a slight rise of ground. With infinite caution he raised himself, risking a glance over an out-cropping of rock. The stunted trees ended just ahead. Beyond, he could make out the dim contour of rolling desert. Flap-jack country. He got to his feet, clambered over the stone—still hot after a day of tropical heat—and moved forward twenty yards. Around him he saw nothing but drifted sand, palely visible in the starlight, and the occasional shadow of jutting shale slabs. Behind him the jungle was still. right this time.... There was a sudden rasp, like leather against concrete, and a flurry of sand as the Flap-jack charged. Retief rolled aside, then lunged, threw his weight on the flopping It scrabbled with prehensile fringe-tentacles for a grip on Retief's The Flap-jack reversed its tactics, went limp. Retief grabbed, felt a The alien went wild. Retief hung on, dug the thumb in deeper. The Flap-jack fell still, only its fringes rippling slowly. Retief "Now we understand each other," said Retief. "Take me to your leader." Twenty minutes' walk into the desert brought Retief to a low rampart of thorn branches: the Flap-jacks' outer defensive line against Terry Flap-jacks. He sat down and eased the weight of his captive off his back, but kept a firm thumb in place. If his analysis of the situation was correct, a Flap-jack picket should be along before too long.... A penetrating beam of red light struck Retief in the face, blinked off. Retief tightened his grip on the alien. He could see a dark shape now, out. Retief cocked his head, frowning. "That's fine," Retief said. "I'm here to arrange a prisoner exchange." "The word of a gentleman is sufficient." Retief released the alien. It "Think nothing of it," Retief said. "We diplomats are trained to crawl." Retief turned. An immense Flap-jack, hung with crimson trappings, "Avoid it?" Retief heard a low humming coming from the speaker in the "I'm Retief." Hoshick waited expectantly, "... of the Mountain of Red "Take place, Retief," said Hoshick. "I hope you won't find our rude raised a tube, manipulating it deftly with his fringe tentacles. Retief "Oh, by all means," Retief said. "No atomics. As you pointed out, "Delicious," said Retief. "I wonder. Have you considered eliminating "As a matter of fact," said Retief, "we ourselves seldom use weapons." "My apologies," said Retief. "The—ah—the skirmishform failed to "Sir!" said Retief sternly. "You forget yourself. I, Retief of the Red "I fear I must lay aside the translator now, Retief," said Hoshick. more pleasant it is to observe the action of the skirmishforms from a distance." "I suggest we use Tennessee rules," said Retief. "They're very liberal. "Very well. Shall we begin?" With a rush Hoshick threw himself at Retief, who ducked, whirled, and leaped on the Flap-jack's back ... and felt himself flipped clear by as Hoshick turned on him he jumped to his feet and threw a right around in an arc that connected with Retief's jaw, sent him spinning Retief twisted, tried to roll. The flat body of the alien blanketed Retief's air was running out. He heaved up against the smothering The Flap-jack recoiled. Retief held fast, probed deeper, groping with Retief dug in and the Flap-jack writhed, pulled away. Retief held on, Retief relaxed, released his hold and got to his feet, breathing hard. "Great sport, wasn't it?" said Retief. "Now, I know you'll be eager to Hoshick curled his back in attention. "Retief, you're quite serious? me, Retief," he cried. "This time, in generosity."

<question>:
How did Retief evade the missile?

<options>:
A He used emergency retro-drive
B He flew right at it
C He crashed the skiff
D He altered course to the south

<answer>:

B