Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

[EX Q]: Context: To survive and reproduce, animals must be able to modify their motor behavior in response to changes in the environment. We studied a complex behavior of Caenorhabditis elegans, male mating behavior, which provided a model for understanding motor behaviors at the genetic, molecular as well as circuit level. C. elegans male mating behavior consists of a series of six sub-steps: response to contact, backing, turning, vulva location, spicule insertion, and sperm transfer. The male tail contains most of the sensory structures required for mating, in addition to the copulatory structures, and thus to carry out the steps of mating behavior, the male must keep his tail in contact with the hermaphrodite. However, because the hermaphrodite does not play an active role in mating and continues moving, the male must modify his tail posture to maintain contact. We provide a better understanding of the molecular and neuro-muscular pathways that regulate male tail posture during mating.', 'Genetic and laser ablation analysis, in conjunction with behavioral assays were used to determine neurotransmitters, receptors, neurons and muscles required for the regulation of male tail posture. We showed that proper male tail posture is maintained by the coordinated activity of opposing muscle groups that curl the tail ventrally and dorsally. Specifically, acetylcholine regulates both ventral and dorsal curling of the male tail, partially through anthelmintic levamisole-sensitive, nicotinic receptor subunits. Male-specific muscles are required for acetylcholine-driven ventral curling of the male tail but dorsal curling requires the dorsal body wall muscles shared by males and hermaphrodites. Gamma-aminobutyric acid activity is required for both dorsal and ventral acetylcholine-induced curling of the male tail and an inhibitory gamma-aminobutyric acid receptor, UNC-49, prevents over-curling of the male tail during mating, suggesting that cross-inhibition of muscle groups helps maintain proper tail posture.
Answer: Our results demonstrated that coordination of opposing sex-specific and core muscle groups, through the activity of multiple neurotransmitters, is required for regulation of male tail posture during mating. We have provided a simple model for regulation of male tail posture that provides a foundation for studies of how genes, molecular pathways, and neural circuits contribute to sensory regulation of this motor behavior.
[EX A]: Does coordination of opposing sex-specific and core muscle groups regulate male tail posture during Caenorhabditis elegans male mating behavior?

[EX Q]: Context: Decisions involving risk often must be made under stressful circumstances. Research on behavioral and brain differences in stress responses suggest that stress might have different effects on risk taking in males and females.', 'In this study, participants played a computer game designed to measure risk taking (the Balloon Analogue Risk Task) fifteen minutes after completing a stress challenge or control task. Stress increased risk taking among men but decreased it among women.
Answer: Acute stress amplifies sex differences in risk seeking; making women more risk avoidant and men more risk seeking. Evolutionary principles may explain these stress-induced sex differences in risk taking behavior.
[EX A]: Does acute stress increase sex differences in risk seeking in the balloon analogue risk task?

[EX Q]: Context: To study the role of peroperative transrectal ultrasonography (peTRUS) for the dissection of the bladder neck during robot-assisted laparoscopic prostatectomy (RALP).', 'Integrated peTRUS in the da Vinci S system (Intuitive Surgical, Sunnyvale, CA, USA) was used for bladder neck identification and dissection in the initial 80 patients with clinically localized prostate cancer operated by two urologists. The clinical and pathological results were compared with the initial 80 patients who had RALP with no peTRUS. The location of positive margins was recorded.', "The operative duration, blood loss, hospital stay, catheter dependency, clinical and pathological T-stage and Gleason sum score were no different between the groups. The prostate-specific antigen level at time of diagnosis was slightly higher for patients in the peTRUS group. Basal surgical margins (bladder neck and basal areas of both prostate lobes) were positive for tumour in 9.1% and 2.3% of patients treated without and with peTRUS, respectively (P = 0.001). Although the use of peTRUS improved the basal margin rate in the initial 30 patients in each group, it did not in the last 30 in each group, when the urologist's experience apparently improved. In a multivariate analysis the use of peTRUS and pathological T-stage were the best predictors of basal margin status. Pad use at 6 months after surgery was similar for both groups.
Answer: peTRUS during RALP decreased the positive surgical margin rate at the base of the prostate during the initial experience of RALP.
[EX A]:
Does peroperative transrectal ultrasonography-guided bladder neck dissection ease the learning of robot-assisted laparoscopic prostatectomy?