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

<passage>:
the U.S. copyright on this publication was renewed.] Score one or one million was not enough for the human race. It had to be all or nothing ... with one man doing every bit of scoring! inches short of disaster, buzzed angrily and retreated to the shelter of a nearby broadleaf, where it executed another half roll and hung upside down, watching its intended meal with avid anticipation. him. He had been bitten once already and the memory of those paralyzed three minutes while the bloodsucker fed was enough to last him for Niobe—a perfect name for this wet little world. The Bureau of Extraterrestrial Exploration couldn't have picked a better, but the funny thing about it was that they hadn't picked it in the first place. Niobe was the native word for Earth, or perhaps "the world" would be planet and its mythological Greek namesake had much in common. Niobe, like Niobe, was all tears—a world of rain falling endlessly to the sea. Trekking on Niobe was an amphibious operation unless one stayed in the highlands—a perpetual series of fords and river crossings. And it was hot, a seasonless, unchanging, humid heat that made a protection suit an instrument of torture that slowly boiled its wearer was irresistible temptation to Niobe's bloodsucking insects. Many of these were no worse than those of Earth, but a half dozen species were deadly. The first bite sensitized. The second killed—anaphylactic was, it was better to boil in it than die without it. He looked at Kron squatting beside the trail and envied him. It was Like the dominant species on every intelligent planet in the explored Kron resembled humanity—but there were differences. Niobians, although excellent swimmers, were land dwellers and ate anything. Lanceford couldn't repress an involuntary shudder at some of the things they apparently enjoyed. Tastes differed—enormously so between Earthmen and Niobians. There was no doubt that the native was intelligent, yet he, like the rest of his race, was a technological moron. It was strange that a race which had a well-developed philosophy and an amazing comprehension of managed to last through the others and this one could be no worse. At that, even an airless room full of natives was preferable to spending a night outside. And the sith wouldn't follow them. It didn't like like to get caught away from shelter during the night. The three moved onward, immersed in a drumming wilderness of rain—the Niobian sliding easily over the surface of the mud, the Earthman perish from sheer propinquity. One could never honestly say that familiarity with the odor of a Niobian bred contempt—nausea was the and, after a single eye-filling stare, turned back again. Niobians curiosity to draw attention, one searching look was all their customs allowed. Thereafter, they minded their own business. In some ways, system could handle the unsavory mess, but his taste buds shrank from the forthcoming assault. What the natives classed as a delicate and elusive flavor was sheer torture to an Earthman. Possibly there was some connection between their inefficient olfactory apparatus and their odd ideas of flavor, but whatever the physical Niobians eyed the reeking semi-solid eagerly. No meal on Niobe was considered worthy of the name unless a generous helping of vorkum started it off. An entree like that could ruin the most rugged human appetite, but when it was the forerunner of a main dish of highly spiced barbecue, Kron offered. The Niobian never seemed to learn. At every meal they had eaten during their past month of travel on Niobe, Kron had persistently refused. After all, there were limits. But polite convention required that he eat something, so he took a small portion of the barbecued meat and dutifully finished it. The sitting in on a Niobian meal and this one was worse than usual. Huge beat off the attacks of the blood-suckers. The climax was horror. One of the siths slipped through his frantically beating hands and bit him on the face. The shocking pain of the bite world was alien. Occasionally danger tended to recede into a background world. He sighed and lay back. There wasn't anything more to do now. All he The Bureau of Extraterrestrial Exploration had discovered Niobe barely three years ago, yet already the planet was famous not only for its live and work on Niobe without having to hide beneath domes or behind that Niobe was crash priority—a world that For Niobe was a made to order herbarium for a swampland plant called Terra and Lyrane. But these two worlds were the seats of human and The result was that nobody was happy until Niobe was discovered. considerable grumbling. In the nick of time, Niobe appeared upon the scene, and Niobe had environment in abundance! spurred on by the people who composed it. The exploration of Niobe proceeded at all possible speed. With so many considerations weighed against them, what did a few lives matter? For the sake of the billions Seemed rather silly—a Class VII civilization using techniques that were old during the Dark Ages before the Atomic Revolution, sending foot parties to explore a world in the chance that they might discover something that the search mechs missed—anything that would shorten the lag time. It was incomprehensible, but neither Sims nor the BEE would do a thing like this without reason. And whatever it was, he wasn't going to worry about it. In fact, there wasn't much time left to worry. The reaction was observably and painfully worse. It was important that the news of his death and the specimens he had It was a crime that handie-talkies couldn't be used here on Niobe, but their range, limited at best, was practically nonexistent on a planet reacted like his own people. He scratched his head and pulled thoughtfully at one of his short ears. had denied his help for weeks, and Niobians simply didn't disregard It went to extremes—even with life at stake, a person's wishes and beliefs must be respected. Always and forever, they held to their own ways, trying with insensate stubbornness to mold nature to their will—and when nature overcome their artificial defenses, they died, stubborn, unregenerate, inflexible to the end. They were odd, these humans—odd and a little frightening. was uncomfortable, like inhaling liquid fire, and then there was the constant desire to cough and the physical inability to do so. to himself. He listened. There might be something important in these dying murmurings, something that might explain their reasons for being good." Kron's eyes were brilliant. He hummed softly under his breath, the Niobian equivalent of laughter. "And all the time we thought—" he began, and then broke off abruptly. Already too much time was wasted without losing any more in meditating upon the ironies of life. He was aware of the incredible complexity and richness of Kron's thoughts, of oddly sardonic laughter, of pity and regret that such a little thing as understanding should cause death and suffering through its lack, of bewildered admiration for the grim persistence of the alien Earthmen, mixed with a wondering curiosity about what kept them here—what the true reasons were for their death-defying persistence and stubbornness—of an ironic native paraphrase for the Terran saying, "Every man to his own taste," and a profound speculation upon what fruits might occur from true understanding between his own race and the aliens. It was a strangely jumbled kaleidoscopic flash that burned across the discussion and thought—a decision of which every Niobian was aware and with which most Niobians agreed.

<question>:
How did the planet of Niobe compare to others that Earth was exploring?

<options>:
A It was be explored as a courtesy to see what could be done to help their planet from spinning into their sun
B It was one of the least interesting to Earth, but was a personal mission for the narrator
C It was one of several planets being considered for colonization
D It was one of the most interesting

<answer>:

D