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 redeem himself by capturing Koerber whose ships were the scourge of the Void. But his marooned on a rogue planet—fighting to save himself from a menace weapons could not kill. Planet Stories Fall 1944. Extensive research did not uncover any evidence that I'm afraid I can offer no competition to the beauties of five planets—or is it six? With regret I bow myself out, and knowing me as you do, you'll understand the futility of trying to convince me again. Anyway, him cold. He wanted solitude, somewhere to coordinate his thoughts in silence and salvage something out of the wreck of his heart, not to speak of his career. But Venus, in the throes of a gigantic boom True, Koerber's escape from the I.S.P. net had not quite been his that almost surrounded the space pirate. under the ineffable illumination of the Chamber. It cost a young fortune. But to pleasure mad, boom-ridden Venus, a fortune was a bagatelle. Only it had cost Dennis Brooke far more than a handsome, red-haired spacer, but from the table across, came the tinkling sound of a fragile glass being crushed in a powerful hand, and a muffled Martian curse. Without warning, the Martian was on his I'm not mistaken this chap's a member of Bren Koerber's pirate crew. Koerber himself to set me right with the I.S.P. again—you don't know gently. "We'll say you captured him, and if he's Koerber's, the credit's yours. A trip to Terra's what you need, Venus for you is a hoodoo!" The stern, white haired I.S.P. Commander behind the immense Aluminil Koerber's henchmen—has given us a line as to his present orbit of delicate piece of work here on Terra that only a very beautiful, and very clever young lady could perform. And," he paused, grimacing, "somewhere between Venus and Terra, the interplanetary spacer bringing her and several other passengers, began to send distress signals. overdue. All passengers, a cargo of radium from Venus worth untold millions, the spacer itself—seem to have vanished." Dennis Brooke's space-tanned features had gone pale. His large hazel of Koerber sent a wave of anguish that seared through him like an Koerber, or forfeit my life!" Venus with passengers and cargo, as far as we could contact the vessel in space. This, Dennis," the Commander emphasized his words, "is your chance to redeem yourself!" He fell silent, while the viso-screen began to show a crowded space port on Venus, and a gigantic passenger spacer up-tilted in its cradle. They watched the parabola it made in its trajectory as it flashed into space and then fell into orbit there beyond the planetary attraction of Venus. On the three-dimensional viso-screen it was uncannily real. A flight that had taken many hours to accomplish, was shortened on the viso-screen to a matter of minutes. They saw the great, proud Tiny on the viso-screen, the fatal spots must have been huge in actuality. To the Commander of the I.S.P., and to Captain Brooke, it was an old story. Atom-blasts were pitting the spacer's hull with Terra in emergency spacers, or are picked up in space by other transports ... and sometimes son ... well, as you know, sometimes of ice. "Right now, if you wish. We have a new cruiser armored in beryloid with phantom ship that seemed to have vanished from space, and an equally elusive pirate whose whereabouts were hidden in the depths of inner planets, where men spent sleepless nights in eternal vigilance against stray asteroids and outlaw crews of ruthless vandal ships. Even viso-screen in the control room. Instantly the I.S.P. cruiser came to life. In a burst of magnificent speed, the cruiser literally devoured the space leagues, until the spacer became a flashing streak. On the viso-screen, the speck grew larger, took on contours, growing and all but George Randall, the junior member of the crew had served his apprenticeship among the inner planets, Mars, Venus and Terra. He felt nauseated at the very thought of going out there in that vast abyss of space. His young, beardless face, with the candid blue eyes went pale fired by Koerber!" He tried to maintain a calm exterior, but inwardly resolve to deal with Koerber once and for all remained to him. Tom Jeffery, the tall, angular and red-faced Navigator, whose slow, prayed that it were Koerber. It had to be! No interplanetary passenger but a pirate crew with swift battle cruisers could dare! This was the dangerous asteroid belt, where even planetoids drifted in eccentric uncharted orbits. unmistakably for what it was—a pirate craft, it showed by its sudden maneuver that it had detected the I.S.P. cruiser. For it had described a parabola in space and headed for the dangerous asteroid belt. As if asteroids, it plunged directly into the asteroid drift, hoping to lose succeeded, no I.S.P. patrol ship would have dared to venture into such from starboard. Koerber's powerful spacer reeled, dived and came up midship showed on Koerber's Cruiser which trembled as if it had been he came up, a lone shell struck. At such close range, super-armor was ripped, second armor penetrated and the magnificent vessel shook under It was then that Dennis Brooke saw the immense dark shadow looming immediately behind Koerber's ship. He saw the pirate cruiser zoom doomed, he tried to draw the I.S.P. Cruiser down with him. A powerful magnetic beam lashed out to spear the I.S.P. Cruiser. maneuvered to avoid the beam. Again Koerber's beam lashed out, as he Koerber's lashing magnetic beam touched and the I.S.P. ship was caught, forced to follow the pirate ship's plunge like the weight at the end of a whiplash. Koerber's gunners sent one parting shot, an atom-blast that Beneath them, growing larger by the second, a small world rushed up to meet them. The readings in the Planetograph seemed to have gone crazy. It showed diameter 1200 miles composition mineral and radio-active. Gravity seven-eighths of Terra. It couldn't be! Unless perhaps this unknown planetoid was the legendary core of the world that at one time was supposed to have existed between Jupiter and Mars. Only that could possibly explain the incredible gravity. a crash. Far in the distance they could see Koerber's ship preceding them in a free fall, then the Planetoid was rushing up to engulf them. a man didn't exert himself. To the silent crew of the I.S.P. Cruiser, the strange world to which Koerber's magnetic Beam had drawn them, the cruiser, had a poisonous, deadly look. As far as their eyes could Scotty eyed the damage. The atom-blast had penetrated the hull into shot of Koerber's severed our main rocket feed. I had to use the "I think we got Koerber, though," he said at last. "While Tom was doing "To hell with Koerber!" Tom Jeffery exploded. "You mean we're stuck in failed to be at his battle-station in time of emergency, had no place in the I.S.P. "Considering the gravity of this planetoid," Dennis Brooke said thoughtfully, "it's going to take some blast to get us off!" "Maybe we can locate a deposit of anerioum or uranium or something for to find out what happened to Koerber's ship. I must know," he said in a A figure appeared in the slanting doorway of the ship in time to hear

<question>:
What caused the shadow behind Koerber's ship

<options>:
A A transport ship
B A large planet
C An asteroid
D A small planet

<answer>:

D