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

<passage>:
Planet Stories Fall 1944. Extensive research did not uncover any evidence that in-coming pilots and crewmen could relax before leaving for another Grannie Annie! I barged across the lounge and seized her hand. "Grannie Annie! I haven't seen you in two years." "Hi, Billy-boy," she greeted calmly. "Will you please tell this fish-face to shut up." and Grannie Annie her usual whisky sour—I waited until she had tossed But to me she was still Grannie Annie, as old-fashioned as last year's more. Her annual income totaled into six figures, and her publishers sat back and massaged their digits, watching their earnings mount. novel, and the locale was the desert of Mars, she packed her carpet bag and hopped a liner for Craterville. If she cooked up a feud between two "It wasn't Guns , it was and it wasn't Ganymede Pluto ." I grinned. "All complete, I'll bet, with threats against the universe and beautiful Earth heroines dragged in by the hair." Up on the wall a clock chimed the hour. The old woman jerked to her feet. "I almost forgot, Billy-boy. I'm due at the Satellite Theater in ten minutes. Come on, you're going with me." Before I realized it, I was following her through the lounge and out to the jetty front. Grannie Annie hailed a hydrocar. Five minutes later we Satellite . that made Swamp City the frontier post it is. In front was a big sign. It read: ONE NIGHT ONLY DOCTOR UNIVERSE AND HIS NINE GENIUSES THE QUESTION PROGRAM OF THE SYSTEM "Sit here," she said. "I'm sorry about all this rush, but I'm one of the players in this shindig. As soon as the show is over, we'll go stage steps and disappeared in the wings. yet." The piano struck a chord in G, and the curtain went rattling up. On the stage four Earthmen, two Martians, two Venusians, and one Mercurian sat on an upraised dais. That is to say, eight of them sat. The "As most of you are familiar with our program, it will be unnecessary to give any advance explanation. I will only say that on this stage are nine visi sets, each tuned to one of the nine planets. At transmitting sets all over these planets listeners will appear and voice questions. These questions, my nine experts will endeavor to answer. For every question missed, the sender will receive a check for one thousand planetoles . From the left wing Grannie Annie appeared. She bowed and took her place Doctor Universe nodded and turned to Grannie Annie who had raised her It grew a little tiresome after a while and I wondered why Grannie had Moments later an official hydrocar roared up and a dozen I.P. men rushed out and scattered the crowd. But a few stragglers lingered to Grannie Annie came out from behind the box office then. She took my arm "Billy-boy, did you see the way that crowd acted?" ought to clamp down." "The I.P. men aren't strong enough." Death In The Atom , hit the stands last January," she began. "When it was finished I had planned to take a six months' vacation, but those fool publishers of mine insisted I do a sequel. Well, I'd used Mars and Pluto and Ganymede as settings for novels, so for this one I decided on Venus. I went to Venus City, and I spent six weeks in-country. I got some swell background material, and I met Ezra Karn...." or cathode rays with negatively charged electrons. and lack of energy. As the period of exposure increases, this condition develops into a sense of impotence and a desire for leadership or a thousand times more subtle and more powerful than any known drug." I was sitting up now, hanging on to the woman's every word. "Now in 2710, as you'd know if you studied your history, the three planets of Earth, Venus, and Mars were under governmental bondage. The cruel dictatorship of Vennox I was short-lived, but it lasted long immediate. Representative government, individual enterprise, freedom followed." Grannie Annie lit a cigarette and flipped the match to the floor. I said, "So what?" times more potent and is transmiting it en masse ." Zinnng-whack! "All right!" A heat ray! Grannie Annie leaped to her feet, grasped my arm and raced for the threw over the starting stud. An instant later we were plunging through the dark night. Six days after leaving Swamp City we reached Level Five, the last outpost of firm ground. Ahead lay the inner marsh, stretching as far as We had traveled this far by ganet , the tough little two headed pack had its motor instantly destroyed, of course, by the magnetic force belt that encircled the planet's equator. Now our drivers changed to boatmen, and we loaded our supplies into three clumsy jagua canoes. It was around the camp fire that night that Grannie took me into her confidence for the first time since we had left Swamp City. see, I'm positive the Green Flames have never been removed from the ship." Sleep had never bothered me, yet that night I lay awake for hours tossing restlessly. The thousand sounds of the blue marsh droned steadily. And the news broadcast I had heard over the portable visi talons raked my clothing. Again it came, and again I rolled swiftly, appeared. Grannie gave a single warning: "Stand still!" Grannie Annie fired with deliberate speed. in the swamp. Harmless in its wild state, but when captured, it can be trained to pursue a quarry until it kills. It has a single unit brain and follows with a relentless purpose." "Then that would mean...?" tent and faced me with earnest eyes. "Billy-boy, our every move is being watched. From now on it's the survival of the fittest." The following day was our seventh in the swamp. The water here resembled a vast mosaic, striped and cross-striped with long winding ribbons of yellowish substance that floated a few inches below the a matter of seconds. At high noon by my Earth watch I sighted a low white structure on one civilization entirely. Grannie Annie came to the point abruptly. When she had explained the that's manifested by laughing. But just what it is that makes them laugh, I don't know." Food supplies and fresh drinking water were replenished at the hut. "The Doctor Universe program," he said. "I ain't missed one in months. You gotta wait 'til I hear it." Grannie frowned in annoyance, but the prospector was adamant. He camped that night on a miserable little island where insects swarmed about us in hordes. The next day an indefinable wave of weariness and despondency beset our entire party. I caught myself musing over the futility of the venture. Only the pleadings of Grannie Annie kept me from turning back. On the morrow I realized the truth in her warning, that all of us had been exposed to the insidious radiations. After that I lost track of time. Day after day of incessant rain ... of steaming swamp.... But at length we reached firm ground and began our advance on foot. suspended between them was a network of copper wire studded with white insulators. Grannie gazed a long moment through binoculars. "Billy-boy, take three Venusians and head across the knoll," she ordered. "Ezra and I will circle in from the west. Fire a gun if you strike trouble." "Up we go, Billy-boy." Heat gun in readiness, Grannie Annie began to swing slowly to and fro. Grannie stamped her foot. "It's maddening," she said. "Here we are at the crux of the whole matter, and we're powerless to make a single move."

<question>:
How long did Billy-boy and Grannie Annie travel after heat ray attack?

<options>:
A Until January, when Death In The Atom hit stands
B six weeks
C Until dark when the arrived at the camp fire
D six days

<answer>:

D