question:  Which description is the best representation of Yrtok's role in the story?
context: It may be useful to discover temporary sources in this area of natural foods." The Planetary State of Haurtoz had been organized some fifteen light-years from old Earth, but many of the home world's less kindly techniques had been employed. Lack of complete loyalty to the state was likely to result in a siege of treatment that left the subject suitably "re-personalized." "You will scout in five details of three persons each," Chief Slichow said. "Every hour, each detail will send one person in to report, and he will be replaced by one of the five I shall keep here to issue rations." The maintenance of a proper viewpoint was a necessity if the Planetary State were to survive the hostile plots of Earth and the latter's decadent colonies. Kolin found himself in a group with Jak Ammet, a third cook, and Eva Yrtok, powdered foods storekeeper. Since the crew would be eating packaged rations during repairs, Yrtok could be spared to command a scout detail. Chief Slichow emphasized that the keepers of rations could hardly, in an emergency, give even the appearance of favoring themselves in regard to food. Yrtok, a dark, lean-faced girl, led the way with a quiet monosyllable. Only a sparse creeper grew along their way, its elongated leaves shimmering with bronze-green reflections against a stony surface; but when they topped the ridge a thick forest was in sight. Yrtok and Ammet paused momentarily before descending. For all Kolin could tell, he and the others were isolated in a world bounded by the rocky ridge behind them and a semi-circle of damp trees and bushes several hundred meters away. "Be a job to find anything edible here," grunted Ammet, and Kolin agreed. Yrtok paused to examine some purple berries glistening dangerously on a low shrub. "We'd better explore along the edge," decided Yrtok. Kolin straightened up and beckoned to Yrtok. As he reached her, whatever Yrtok was examining came to life and scooted into the underbrush with a flash of greenish fur.
output:  Her fall leads Kolin to find Ashlew
options:  She figured out what was wrong with Ammet when he fell.  She was the reason they had a quality water supply.  She found the purple berries, an important source of food for the stranded crew.  Her fall leads Kolin to find Ashlew