question:  Why is Brandt interested in The Comerford?
context: [Transcriber's Note: This etext was produced from Astounding Science-Fiction April 1942. Extensive research did not uncover any evidence that the U.S. copyright on this publication was renewed.] Androka had arrived on board the Comerford the day before she sailed from Norfolk. With him came a boatload of scientific apparatus and equipment, including a number of things that looked like oxygen tanks, which were now stored in the forward hold. Androka had watched over his treasures with the jealous care of a mother hen, and spent hours daily in the room in the superstructure that had been assigned as his laboratory. He was overfriendly with a black-browed bos'n's mate named Joe Bradford—the worst trouble maker on board. Nevertheless, his taut face, restless, searching eyes, and eternally nervous manner got Curtis' goat. Nelson had no answering smile, although there had been a great deal of good-natured joking aboard the Comerford ever since the navy department had sent the scientist on board the cruiser to carry on his experiments. "But this storm, sir!" Nelson avoided Curtis' friendly eyes and slipped out from under his arm. "Not that I've lost confidence in you, Nels, but just because you asked for it!" Nelson's estimate, I'm checking back," he declared, frowning at the two papers and hastily rechecking his own figures. With all these rocks and islets—" "Radio?" repeated the little Czech, thrusting his face between the other two, in his independent fashion that ignored ship's discipline. Then he hastened to the radio room, with Nelson at his heels, and the Czech trotting along behind. I have shattered them around your ship, just as I can eventually shatter them all over Central Europe! For the next two hours, no radio messages can enter or leave my zone of radio silence—of refracted radio waves, set up by my little station on one of the neighboring islets!" The answer came back: "Bearings north east by a quarter east, U. S. Cruiser Comerford !"
output:  He wants to use its zone of silence to apprehend the Carthusia.
options:  He is holding the ship ransom as revenge for what American has done to Germany.  He is holding the ship ransom for Boarts—black diamonds.  He wants to use its zone of silence to apprehend the Carthusia.  He wants to use its zone of silence to trick other ships into crashing on the islet.