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

<passage>:
R X never die. Of course, it was up to the Earth doctor to see that he didn't! [Transcriber's Note: This etext was produced from ship from HQ in Standard GPP Contract code for crash priority, which meant Top Grade Planetary Emergency, and don't argue about it, fellows, just get there, fast. Red Doctor Sam Jenkins took one look at the gyros hummed, bearings were computed and checked, and the General Practice Patrol ship Lancet VI planet didn't quite register with anybody, just then. Ten minutes later the Red Doctor reached for the results of the Initial Green Doctor Wally Stone frowned and scratched his whiskered chin. caught the black-striped card. "Class VI planet ... a plague spot! How can we get a crash-call from the folks on Morua II didn't want a Contract with Hospital Earth. And they're still in the jungle, as far as their medicine goes. Witch doctors and spells." He tossed the Info-card down the chute with a they couldn't possibly know." The surgeon in the green undershorts chewed his lip. "Looks like "Obviously." "Well, what are we doing on automatics? We're not "Law be damned," Stone cried. "File a protest with HQ. Cancel the We don't do that in the General Practice Patrol, remember? I don't know how Morua II got the code, but they got it, and that's all the farther we're supposed to think. We answer the call, and beef about it later. It had always been that way. Since the first formal Medical Service Earth had laboriously built its reputation on that single foundation stone: immediate medical assistance, without question or hesitation, whenever and wherever it was required, on any planet bound by Contract. That was the law, for Hospital Earth could not afford to jeopardize a Contract. In the early days of galactic exploration, of course, Medical Services was only a minor factor in an expanding commercial network that drew transport, and in production techniques—but Earth stood unrivaled in its development of the biological sciences. Wherever an Earth ship landed, the crew was soon rendering Medical Services of one sort or another, whether they had planned it that way or not. On Deneb III the Medical Service Contract was formalized, and Hospital Earth came Practice Patrol were dispatched—"Galactic Pill Peddlers" forging a chain of Contracts from Aldebaran to Zarn, accepting calls, diagnosing ills, arranging for proper disposition of whatever medical problems they came across. Serious problems were shuttled back to Hospital Earth more frequently the GPP crews—doctors of the Red and surgery—were able to handle the problems on the spot and by themselves. It was a rugged service for a single planet to provide, and it was physicians, eh?" He eyed them up and down as though he disapproved of Doc." Jenkins nodded grimly. "What does it look like to you?" hulk with inquiring fingers. "If it's a viremia, we're cooked," Stone whispered. "None of the drugs cross over—and we won't have time to culture the stuff and grow any "What about your own doctors?" the humors and drive forth the spirits of the Pox like devils." He "We'll need supplies and information from our ship. We'll have to consult your physicians. We'll need healthy Moruans to examine—" "But you will cure him," Aguar said. "But what do you think we're going to do?" the surgeon wailed, back Lancet . "Sam, we can't him. If he didn't die naturally we'd kill him for sure! We can't go near him without a Bio-survey—look what happened on Baron when they tried it! Half the planetary population wiped out before they realized that the antibiotic was more deadly to the race than the virus was...." just to keep alive for a while." oxygen-breathers, which means they manage internal combustion of carbohydrates, somehow. From the grey skin color I'd guess at a cuprous or stannous heme-protein carrying system. They're carnivores, but god knows what their protein metabolism is like—Let's get going on some of these specimens Aguar has rounded up for us." They dug in frantically. Under normal conditions a GPP ship would send in a full crew of technicians to a newly-Contracted planet to make the initial Bio-survey of the indigenous races. Bio-chemists, physiologists, anatomists, microbiologists, radiologists—survey workers from every Service would examine and study the new clients, take them apart cell by cell to see what made them tick. Certain basic principles were always the same, a fact which accelerated the program considerably. Humanoid or not, all forms of life had basic qualities in common. Biochemical reactions were biochemical reactions, whether they happened to occur in a wing-creature of Wolf IV or a doctor from Sol III. Anatomy was a broad determinant: a jelly-blob from compared, and the information used in combating native disease. Given no major setbacks, and full cooperation of the natives, the job only took about six months to do— For the crew of the Lancet herded cringing Moruan "volunteers" into the little ship's lab. Jenkins handled external examinations and blood and tissue chemistries Stone ran the X-ray and pan-endoscopic examinations. After four grueling hours the Red Doctor groaned and scowled at the growing pile of data. "Okay. It seems that they're vaguely humanoid. And that's about all we the Red Doctor cut him off. "It violently on the idea of a Hospital Earth Contract, eh? Couldn't risk After you show us." promises, pills and post-mortems. That's the Medical service for you." Sam grinned. "Maybe you should operate on him. That "No thanks, not me. This is a medical case and it's all yours. What do you want me to do?" "Stay here and try your damnedest to get through to HQ," said Sam poke holes in the healthy ones! And then you send in braziers, Red Doctor Jenkins drew the wizard aside. "First we brewed witches' root for seven hours and poured it over his at the foot of the bed and beat His Eminence steadily for one hour out fighting, but the tube went down. The Red Doctor ground three white he found a large mortar which he set down on the floor. Squatting behind it, he began tapping it slowly with the pestle, in perfect Eminence and the plink-plink of the pestle on the mortar. The flask of Jenkins motioned to Kiz. "His pulse—quickly!" Kiz scampered gratefully over to the bedside. "A hundred and eighty," he whispered. outsider." He motioned toward the mortar. "Can you do this?" They woke him once, hours later, to change the intravenous solution, and he found Kiz still intently pounding on the mortar. Jenkins mortar, and began stripping off the sodden bedclothes. "Blankets, now—plenty of them." The plink-plink rose to a frantic staccato as Jenkins checked the patient's vital signs, wiped more sweat from his furry brow. Quite Jenkins snatched the mortar from Kiz, and with a wild flourish smashed "So am I," said the Green Doctor suspiciously. "With what? Incantations?" "Oh, the incantations were for the doctors ," said Jenkins. "They expected them, obviously, since that was the only level of medicine Bio-survey we were hamstrung. But whatever the Pox is, it obviously involves fever, starvation and dehydration. I knew that His Eminence could assimilate carbohydrates, and I took a long gamble that an "Not quite," said the Red Doctor. "You're forgetting that I had thousand years ago. Without it, Hospital Earth might just as well pack

<question>:
Why did the Earth doctor use the mortar and pestle?

<options>:
A To help the local doctor understand the treatment
B To keep the IV drip going
C To prepare medication
D As part of the bio-survey

<answer>:

A