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

<passage>:
to “cook” in an atomic reactor and soak up radioactivity. CHAPTER ONE to have finished it, but the bar of morning sunlight Still, it doesn’t take so very much radioactivity He heard his father’s heavy footsteps in the “What do you mean, send it somewhere?” and the gray hair at his temples didn’t add much age, although Eddie knew it had been from the kitchen. materials kept building up in his mind. By the clicking like everything.” rocks. Suddenly the Geiger counter began “Well, you were together most of the day,” where you might strike some radioactivity.” It was a balmy evening. On such evenings, and went back down the hallway toward the “Oh, I figured you’d be through by now,” Eddie apologized, following her inside. or two, he was fairly safe. During the summer months his freckles got so thick and dark that didn’t seem as cheerful as usual. “Hello, Eddie,” Mrs. Ross said, but she plastered some water on his dark-red hair, pushed a comb through it, and shrugged as it snapped back almost to its original position. “Good evening, Mrs. Ross,” Eddie said. “I—I knowing that even if he missed a spot He grinned into the mirror, reached a a little while about that newspaper write-up.” put fresh ones in after breakfast. He brushed his teeth carefully, taking particular “Right on the front page.” him about letting food gather around the said. “Maybe we could understand more of what it’s all about if you could explain what a day today.” radioisotope is, Eddie.” “Aw, Mom—” around today.” calmly but firmly. “School vacation doesn’t “Well,” Mr. Taylor added, excusing himself from the table, “I’d better be getting over of a new radioisotope today.” The very word excited Eddie. In fact, anything name ‘pile’—from brick pile. Anyway, scattered excited him. He knew something about along the way. Eddie knew that a radioisotope was a material which had been “cooked” in an atomic reactor until it was “hot” with radioactivity. around, but they break apart. They shoot out When carefully controlled, the radiation hit other atoms and split them apart, sending “I’ve heard of chain reactions,” Mrs. Ross asking that particular question was to keep “Well, with all of the splitting up and moving on, “an awful lot of heat builds up. If they from prying deeper into the subject of the out of control.” “Out of control is right,” Teena said. “But the atomic piles control the reaction,” 42 only as much radiation builds up as they want. You can even hear the reactor hum as the radioactive blow up.” replied. several times before, weakening the batteries. “Goodness. Eight feet is a lot of cement.” driven off the coolness which the ocean air “Anything else, Mom?” he asked, returning and the hardest to stop. Alpha and beta over his hasty retreat. “What are you going more he realized it was a little late in the day and doing nothing, there would be an awful that was too long a row to be starting now. radioactive, but can be made radioactive, and with a Geiger counter. 18 in the pile.” tried to make it sound as though he would of the pile, some of them smack into the or something like that. the exercise.” for an early dinner.” then added, “from behind a protective shield, of course. When the material has soaked up say it’s ‘cooked.’” started down the street. “It’s hot,” Eddie said, “but not like if it came out of a stove. By hot, they mean it’s wouldn’t even know it for a while. It would be light-green stucco house and knocked. a radiation burn. That’s a kind of burn you don’t feel, but it destroys your blood cells and “Well, I—I just happened to be going by,” “So that’s what a radioisotope is,” Mrs. Ross said. “It’s like a sponge. Only instead of soaking counter. But maybe you’re too busy.” up water, it soaks up radiation.” a couple of sandwiches or some fruit. “I’m in kind of a hurry.” are strong and dangerous. Others absorb only the kitchen. He felt triumphant about the didn’t know what he was doing and opened up even the mild isotopes are deadly if they’re not handled right.” silverware.” She smiled, putting tiny crinkles in her small, slightly upturned nose. She wore Eddie nodded. It was even more serious was blond all year long, it seemed even lighter in the summer. Eddie couldn’t tell whether the sun had faded it, or whether her deep summer tan simply made her hair look lighter by contrast. Maybe both. it had been developed for curing things or for it depended on how they were handled it carelessly. It was a new isotope—a pretending great injury. “Don’t know why I keep coming over here.” “Or greasing one,” Teena added. a period,” he said. “Did you know that there in a single period printed at the end of a sentence. That’s how small atoms are.” wrapping wax paper around a sandwich. a man’s voice spoke behind him. “What are we talking about, Eddie?” around and standing up. “I didn’t hear you They walked past the college campus, and with light-brown hair which was getting somewhat thin on top. He was usually quite cheerful switched on the Geiger counter. The needle of the dial on the black box wavered slightly. A slow clicking came through the earphones, unusually drawn and sober. He stepped to the a normal background count. There were slight and full of fun, but tonight his face seemed but Eddie knew these indicated no more than “How many in a comma?” Mr. Ross said to was always a mild background count when It wasn’t very funny. I—I’m afraid I don’t feel very funny tonight.” “Sit down, dear,” Mrs. Ross said. “I’ll warm your dinner. You didn’t sound very cheerful the earphones had to speed up until it sounded almost like bacon frying in a hot skillet. ahead on the gauge, and the clicking through There was none of that today. After they “In fact, not good at all.” but to It was midafternoon by the time they arrived and went on down the street toward his knew at once, just seeing the expression on his mother’s face, that something was wrong. “But this morning you said it would be “This morning I didn’t know what might strange urgent tone in it. The door to the den sat stiffly behind his homemade desk, talking rapidly into the telephone. Eddie caught only the last few sketchy words. Then his father years older than he had that very morning. thoughtfully with a pencil, turning it end over end on his desk. and went into the bathroom. He washed hurriedly, the evening papers, anyway.” “Evening papers?” “It did—and it didn’t,” his father said. “What does that mean, Dad?” Eddie asked, puzzled. disappeared.” “Disappeared?” CHAPTER TWO mind, as it was. The main information was in the evening , which Eddie rushed out He took the newspaper to his father to read first. After having finished, Mr. Taylor handed the paper to Eddie and leaned back thoughtfully in his chair. 28 “They’ve got it pretty straight, at that,” Mr. Taylor said, “but I’m afraid this is going to that part of it. The important thing is the Geiger counter was turned on shot. The whole thing was carefully planned Eddie read the newspaper account. The months were few, there was no one on the when the delivery was expected, there would around the building to the front office. It had were barely visible and of no help other arrive a half hour early?” may have had another plan. The way things worked out, they didn’t need to use it. The early delivery and the business of leaving the expected. At least, they took quick advantage a radioisotope,” Eddie said. “Maybe they figured in order to find out exactly how it could best strength of radioisotopes could be controlled

<question>:
What best describes how the overall tone changed from the beginning of the article?

<options>:
A From worrisome to frustrated.
B From apathetic to solemn.
C From lighthearted to tense.
D From upbeat to sympathetic.

<answer>:

C