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

<passage>:
Fiction January 1953. Extensive research did not uncover any evidence that the U.S. copyright on this publication was renewed.] was a question as to which was which. but in spite of his vigilance he had not exposed a film when the outside. "Roll out on the double! I'm going to magnofilm this!" Stryker and Gibson came out of their sleeping cubicles reluctantly, climate. Stryker blinked and yawned as he let himself through the port, "Any sign of the squids yet?" he asked. "They won't show up until the dragons come," Farrell said. He adjusted the light filter of the magnoscanner and scowled at Stryker. "Lee, I tampering with what may be a basic culture-pattern would amount to armed invasion. We'll have to crack that cackle-and-grunt language of theirs and learn something of their mores before we can interfere." gathering, nets and fishing spears in hand, at the edge of the sheltering bramble forest. happen next morning?" Gibson answered him with an older problem, his square face puzzled. "For beyond them by a million years." irritating habit of being right—had worn their patience thin. uprushing of black, octopoid shapes. "The squids," Stryker grunted. "Right on schedule. Two seconds too late, as usual, to stop the slaughter." A barrage of barbed tentacles lashed out of the foam and drove into the behind three of their number who disappeared under the surface like Chattering pink natives straggled past from the shelter of the thorn forest, ignoring the Earthmen, and lined the casting ledges along the stubbornly. "But it's here somewhere, and I'm going to find it. Will either of you be using the scouter today?" Stryker threw up his hands. "I've a mountain of data to collate, and Arthur is off duty after standing watch last night. Help yourself, but you won't find anything." his sleeping cubicle a short time later, leaving Stryker to mutter over his litter of notes. Sleep did not come to him at once a vague sense of something overlooked prodded irritatingly at the back of his consciousness, but it was not until drowsiness had finally overtaken him that the discrepancy assumed definite form. spear-shafts. Which meant that the fishers could not swim, else some would surely have gone in after him. And the Marco's crew had explored Arz exhaustively without finding any slightest trace of boats or of boat landings. The train of association completed itself with automatic logic, almost rousing Farrell out of his "I'll be damned," he muttered. "No boats, and they don't swim. Then how " He fell asleep with the paradox unresolved. the control board hummed softly, its screen blank on open channel. "He's scouring the daylight side now," Stryker said. "Arthur, I'm going He's got that phantom city on the brain, and he lacks the imagination to bullheaded habit of being right. I hope he finds it soon, if it's here. I'll probably be standing his watch until he's satisfied." Stryker looked relieved. "Would you mind taking it tonight? I'm and packed his pipe, settling himself comfortably while Stryker mixed a nightcap before turning in. Later he remembered that Stryker dissolved a tablet in his glass, but at the moment it meant nothing. In a matter of minutes the older man's snoring drifted to him, a sound faintly irritating against the velvety startled. Why two? Why not three or four, or only one? He stepped out through the open lock and paced restlessly up and down on the springy turf, feeling the ocean breeze soft on his face. Three days of dull routine logwork had built up a need for physical action that chafed his temper he was intrigued and at the same time annoyed by the squids, and his desire to understand that relation was aggravated by the knowledge that Arz could be a perfect world for Terran colonization. That is, he thought wryly, if Terran colonists could stomach the weird custom pursued by its natives of committing suicide in pairs. found it not too unnatural until he came to the motivation and the means his whole fabric of speculation fell into a tangled snarl of inconsistencies. He gave it up finally how could any Earthman He went inside again, and the sound of Stryker's muffled snoring fanned his restlessness. He made his decision abruptly, laying aside the magnoscanner for a hand-flash and a pocket-sized audicom unit which he clipped to the belt of his shorts. He did not choose a weapon because he saw no need for one. The torch need help the audicom would summon Stryker. Investigating without Stryker's sanction was, strictly speaking, a breach of Terran Regulations, but— ." mossy ground, sleeping soundly, their triangular faces wholly blank and He worked deeper into the underbrush and found other sleeping couples, but nothing else. There were no humming insects, no twittering last conscious thought was not of his own danger, but of Stryker—asleep and unprotected behind the open port.... could not. muscles of balance and respiration his body was paralyzed. but for some seconds his shuttling mind was too busy to consider the danger of predicament. Whatever brought me here anesthetized me first , he thought. more seconds passed before he gained control of himself, sweating with the effort. He had to get help. If he could switch on the audicom at his belt and call Stryker.... failed. His arm was like a limb of lead, its inertia too great to budge. He against the inner curve of his elbow. He bent his will again toward motion this time the arm tensed a little, enough to send hope flaring Stryker !" The audicom hummed gently, without answer. He gathered himself for another shout, and recalled with a chill of horror the tablet Stryker had mixed into his nightcap the night before. Worn out by his work, Stryker had made certain that he would not be easily disturbed. suggestion of flapping wings. The audicom crackled. The voice that answered was not Stryker's, but outcrop just under the surface of the water, waiting with barbed with shock-born lucidity: . in the Marco ." had any brains. It was under water, of course." In the drinks around, leaving Farrell comfortably relaxed in the padded control chair. The paralysis was still wearing off slowly, easing Farrell's fear of being permanently disabled. Stryker stared. "A marine city? What use would sea-creatures have for buildings?" "None," Gibson said. "I think the city must have been built ages ago—by men or by a manlike race, judging from the architecture—and was submerged later by a sinking of land masses that killed off the original builders and left Arz nothing but an oversized archipelago. The squids "I don't see it," Stryker complained, shaking his head. "The pink "Are cattle, or less," Gibson finished. "The octopods are the dominant race, and they're so far above Fifth Order that we're completely out of armed invasion." "Invasion of a squid world?" Farrell protested, baffled. "Why should surface colonization conflict with an undersea culture, Gib? Why "Because the octopods own the islands too, and keep them policed," the squid-people, making a dry-land canvass of his preserve here to pick sportsmen. The flying-lizards are the game they hunt, and they raise the "Colonization being out of the question, we may as well move on before the octopods get curious enough about us to make trouble. Do you feel up don't think I want to stick here and be used for bait again, do you?" blasted the

<question>:
Of the following options, which technology is not used in the story?

<options>:
A Radio-like communication
B A chemical that prevents a person from moving
C Ships that can submerge to examine deep waters
D Tablets used to enhance rest

<answer>:

C