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

<passage>:
Retief rose, went to the communicator, assisted Miss Meuhl aside. "Listen carefully, Fith," he said. "Your bluff has been called. You don't come in and we don't come out. Your camouflage worked for nine years, but it's all over now. I suggest you keep your heads and resist the temptation to make matters worse than they are." "Miss Meuhl," Fith said, "a peace squad waits outside your consulate. he will be unable—" Retief turned at a sound behind him. Miss Meuhl was at the door, "You can't turn this invitation down," Administrative Assistant Meuhl said flatly. "I'll make that 'accepts with pleasure'." "You can't offend the Groaci," Miss Meuhl said sharply. "Consul Whaffle "I invited them here," Miss Meuhl spoke up. "They are here at my "Are they? Are you sure you meant to go this far, Miss Meuhl? A squad "I don't recall dictating any letters today, Miss Meuhl," Retief said, "Yes," Miss Meuhl said. "You're quite right, Mr. Shluh. Please escort "Did you write all Whaffle's letters for him, Miss Meuhl?" Miss Meuhl blinked behind thick lenses. "Whatever for?" Retief looked thoughtfully at Miss Meuhl. "You've been here on Groac "You think all women are fools, don't you, Mr. Retief?" She turned to Groaci. I certainly hope you're not thinking of openly intruding—" "Why?" "The Groaci are a very sensitive race. They don't welcome outworlders raking up things. They've been gracious enough to let us live down the fact that Terrestrials subjected them to deep humiliation on one occasion." Retief nodded. "Thanks, Miss Meuhl," he said. "I'll be back before "To enjoy a cooling drink," Retief said in Groacian, squatting down at "To not enjoy my poor offerings," the Groacian mumbled. "A pain in the digestive sacs to express regret." decide whether I like it." "To be grappled in by peace-keepers for poisoning of—foreigners." The barkeep looked around for support, found none. The Groaci customers, dish provided. "To shake a tentacle." "The procuring of a cage," a thin voice called from the sidelines. "The displaying of a freak." of contempt. From his bluish throat coloration, it was apparent the creature was drunk. "To swallow your own poison, dispenser of vileness," the drunk whispered. "To find a proper cage for this zoo-piece." He wavered "To be pals," Retief said. "To be kind to dumb animals." "There you are!" Miss Meuhl said, eyeing Retief over her lenses. "There you." "I'm sure you don't. Come along. And bring an official recorder." Two Groaci wearing heavy eye-shields and elaborate crest ornaments to hospital suffering from serious contusions. Questioning of this individual revealed that he had been set upon and beaten by a foreigner. A Terrestrial, to be precise. Investigation by my department indicates that the description of the culprit closely matches that of the Terrestrial Consul." Miss Meuhl gasped audibly. Terrestrial cruiser, the "You'll do as you're told, Miss Meuhl," Retief said quietly. "I'm Somewhat annoying to the Groaci, maybe—at the most. If they were innocent." it." Fith rose paid its visit, and before the arrival of the first Terrestrial diplomatic mission." "This is an internal matter!" Fith cried, in his faint Groacian voice. "The new regime has shown itself most amiable to you Terrestrials. It has outdone itself—" Retief turned a steady look on Miss Meuhl. She closed her mouth. The retracted his eyes, shrank down in his chair. Miss Meuhl opened her "How did they die?" Retief snapped. "Did you murder them, cut their "No!" Fith gasped. "I must correct this terrible false impression at once." "False impression, hell," Retief said. "They were Terrans! A simple narco-interrogation would get that out of any Groacian who saw the parade." "Yes," Fith said weakly. "It is true, they were Terrestrials. But there was no killing." "They're alive?" "Alas, no. They ... died." Miss Meuhl yelped faintly. "Didn't take the trouble to find out, either, did you?" "They fell ill," Fith said. "One by one...." "We'll deal with that question later," Retief said. "Right now, I want "Miss Meuhl," Retief said. "If I don't come back in a reasonable length You're still convinced you can hide the whole thing and forget it. I'm telling you you can't." "You can and you will, Fith," Retief said. "I intend to get to the Fith clacked his mandibles angrily, eye stalks canted aggressively toward the Terrestrial. "Out of deference to your diplomatic status, Terrestrial, I shall "Miss Meuhl," Retief said, "I want you to listen carefully to what I'm going to tell you. I have to move rapidly now, to catch the Groaci off guard." "You're still determined to make an issue of that incident!" Miss Meuhl snorted. "I really can hardly blame the Groaci. They are not a sophisticated race "The Groaci don't know. They're a very cultured, gentle people. You can do irreparable harm to the reputation of Terrestrials if you insist—" "That's my decision," Retief said. "I have a job to do and we're "You and I are in a tight spot, Miss Meuhl. The logical next move for the Groaci is to dispose of both of us. We're the only ones who know what happened. Fith almost did the job this afternoon, but I bluffed him out—for the moment." Miss Meuhl emitted a shrill laugh. "Your fantasies are getting the water in the dispenser. I suggest you stock up, before they shut the supply down. Don't let anyone in, on any pretext whatever. I'll keep in touch with you via hand-phone." "What are you planning to do?" "If I don't make it back here, transmit the sealed record of this blast in here and anyway, they won't make things worse by killing you. A force can be here in a week." "I'll do nothing of the sort! The Groaci are very fond of me! You ... Johnny-come-lately! Roughneck! Setting out to destroy—" "I'll be back in a couple of hours," he said. Miss Meuhl stared after Miss Meuhl, dozing in a chair, awoke with a start. She looked at "I have a message to get off first, Miss Meuhl," Retief said sharply. Miss Meuhl gasped. "You mean you broke in? You burgled the Foreign "This is absolutely the end!" Miss Meuhl said. "Thank heaven I've "I've already done so, Mr. Retief!" Miss Meuhl said harshly. "I've been "He's here now," Miss Meuhl said to the screen. She looked at Retief "I have done my duty, Mr. Retief," Miss Meuhl said. "I made a full Retief looked at her levelly. "You've been a busy girl, Miss Meuhl. Did ignore. I can't afford that, at this moment. Listen, Miss Meuhl," to, Miss Meuhl. But until I've heard get my resignation. If I'm right, that suspension would be embarrassing all around." "You're defying lawful authority! I'm in charge here now." Miss Meuhl Retief ignored Miss Meuhl's fury as he spoke into the recorder.

<question>:
Of what species is Miss Meuhl and Retief?

<options>:
A Groacian
B Unknown
C Human
D Reptile

<answer>:

C