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

<passage>:
Grannie Annie, who wrote science fiction under the nom de plume of Annabella C. Flowers, had stumbled onto a murderous plot more hat, as modern as an atomic motor. She had probably written more drivel in the name of science fiction than anyone alive. But the public loved it. They ate up her stories, and they clamored for more. Her annual income totaled into six figures, and her publishers She was the most completely delightful crackpot I had ever known. "What happened to "It wasn't Guns , it was Pluto ." I grinned. "All complete, I'll bet, with threats against the universe and beautiful Earth heroines dragged in by the hair." "What else is there in science fiction?" she demanded. "You can't have your hero fall in love with a bug-eyed monster." Satellite . zilcon wood seats and dingy atobide lamps. But the place was packed with miners, freight-crew-men—all the tide and wash of humanity that made Swamp City the frontier post it is. DOCTOR UNIVERSE AND HIS NINE GENIUSES 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 Earthman operator. A tall man, clad in a claw-hammer coat, came out from the wings and advanced to the footlights. "People of Swamp City," he said, bowing, "permit me to introduce myself. I am Doctor Universe, and these are my nine experts." There was a roar of applause from the Satellite audience. When it had subsided, the man continued: "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 . "One thing more. As usual we have with us a guest star who will match voice echoed through the theater: " tracto-car." And so it went. Questions from Mars, from Earth, from Saturn flowed in the visi sets. Isolated miners on Jupiter, dancers in swank Plutonian cafes strove to stump the experts. With Doctor Universe offering bantering side play, the experts gave their answers. When they failed, brought me here. And then I began to notice things. The audience in the Satellite signal of Doctor Universe. The spell created by the man was complete. Pompous and erect, he strode back and forth across the stage like a general surveying his army. His black eyes gleamed, and his thin lips the Red Planet. But the thing that happened there was a throw back to Someone shouted, "Yah, yellow-face! Down with all Kagors!" As one 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 shout derisive epithets. Karn...." The old woman paused. "Did you ever hear of the Green Flames?" she asked abruptly. I shook my head. "Some new kind of ..." "It's not a new kind of anything. The Green Flame is a radio-active Alpha rays of this rock are similar to radium in that they consist of streams of material particles projected at high speed. But the character of the Gamma rays has never been completely analyzed. Like those set up by radium, they are electromagnetic pulsations, but they are also a strange combination of Beta or cathode rays with negatively charged electrons. "When any form of life is exposed to these Gamma rays from the Green Flame rock, they produce in the creature's brain a certain lassitude and lack of energy. As the period of exposure increases, this condition develops into a sense of impotence and a desire for leadership or guidance. Occasionally, as with the weak-willed, there is a spirit of intolerance. The Green Flames might be said to be an inorganic opiate, 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. government was to cast out all Green Flames, two of which Vennox had ordered must be kept in each household. The effect on the people was immediate. Representative government, individual enterprise, freedom followed." an old space ship. The hold of that space ship was packed with Green Flames!" if it were true? Green Flames were supposedly destroyed on all planets after the Vennox regime crashed. If a quantity of the rock were in Earth." "I see," I said as she lapsed into silence. "And now you've come to the conclusion that the details of your story were true and that someone is The old woman shook her head. "No, this is a lot bigger than a simple quiz program. The theater crowd was but a cross-section of what is happening all over the System. There have been riots on Earth and Mars, police officials murdered on Pluto and a demand that government by "And you can lay it all to the Green Flames. It seems incredible that a times more potent and is transmiting it en masse ." If it had been anyone but Grannie Annie there before me, I would A heat ray! We had traveled this far by ganet , the tough little two headed pack animal of the Venus hinterland. Any form of plane or rocket would have 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 see, I'm positive the Green Flames have never been removed from the The thing in the darkness turned like a cam on a rod and drove at us purple flame shot outward. A horrible soul-chilling scream rent the resembled a vast mosaic, striped and cross-striped with long winding ribbons of yellowish substance that floated a few inches below the the swamp had undergone a chemical change and evolved into a cohesive multi-celled marine life that lived and died within a space of hours. "Green Flames, eh?" he repeated slowly. "Well yes, I suppose I could Varsoom country, and that isn't exactly a summer vacation spot." "What are the Varsoom?" I asked. "A native tribe?" Karn shook his head. "They're a form of life that's never been seen by Earthmen. Strictly speaking, they're no more than a form of energy." "Dangerous?" "Yes and no. Only man I ever heard of who escaped their country outside because he made 'em laugh." "Laugh?" A scowl crossed Grannie's face. "That's right," Karn said. "The Varsoom have a strange nervous reaction that's manifested by laughing. But just what it is that makes them laugh, I don't know." from turning back. On the morrow I realized the truth in her warning, that all of us had been exposed to the insidious radiations. steel, suspended between them was a network of copper wire studded with white insulators. swing slowly to and fro. Grannie nodded. "Some kind of a broadcasting unit. The Green Flames in the lower hold are probably exposed to a tholpane plate and their radiations stepped up by an electro-phosicalic process." Karn raised the butt of his pistol and brought it crashing against the atomic blast will shatter that wall. It explains why there are no guards here. The mechanism is entirely self-operating. Let's see if the Green Flames are more accessible." vessel's hull were tiers of rectangular ingots of green iridescent ore. Suspended by insulators from the ceiling over them was a thick metal plate.

<question>:
What effects do the Green Flame rocks have?

<options>:
A It makes people lethargic and easily manipulated.
B They spread radioactivity to people and make them ill.
C They influence people to take power over other people.
D They are electromagnetic and shock people.

<answer>:

A