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

<passage>:
The clever and sophisticated simulator I'm playing with started life as a lash-up in an obstetrician's home workshop: a Heath Robinson-style contraption barely recognisable as a model of the human body. But it wasn't at that stage intended as a simulator for training medical staff. Its sole purpose was to test the effectiveness of a novel device called a Tydeman tube. Paradoxically, although the testing equipment, Debra, is now commercially available, the device it was intended to test has yet to reach the market. The inventor of the tube and of Desperate Debra is Dr Graham Tydeman, a consultant in obstetrics and gynaecology at Victoria Hospital in Kirkcaldy, Fife. Only after he'd built Debra did he realise that she might serve a purpose beyond his original intention. His is a decade-long tale of inspired insights, thwarted aims and shifting purposes but with a good outcome. Although the Tydeman tube is still in gestation, Desperate Debra herself is now thriving. which suggests requests for push-ups during unplanned caesareans are far from uncommon. The Tydeman tube is a gadget intended to make this manoeuvre safer and more effective. Creativity and innovation have many unlikely sources. What seems to have inspired Tydeman to develop his device was the characteristic sound of a Wellington boot being pulled free of wet, muddy ground: a slurpy, sucking, gurgling noise. When an impacted foetal head is pulled free of the uterus it's often accompanied by a similar sucking noise, the result of air rushing in between the obstetrician's fingers to fill the space vacated. "What occurred to me years ago was that if the air can't get in, why not put a tube up into the vagina so that it can get in from below the baby's head." From time to time, if he felt he felt the baby might stick, Tydeman would slip a length of sterile silicone tubing through the woman's vagina and up into the womb next to the baby's head. Allowing air in by this route would release any suction forces tending to hold it where it was. Tydeman didn't do much with the idea until 10 years ago when one trainee, who was experiencing real difficulty getting heads out, prompted him to think again about the problem. Around the same time, he met professor of obstetrics Andrew Shennan and consultant midwife Annette Briley, both of the Women's Health Academic Centre at St Thomas's hospital. Between them they came up with a device – the Tydeman tube – to make pushing on the foetus more controlled while simultaneously releasing any vacuum that might be holding it in place. The instrument is made up of a rigid plastic tube opening into a softer silicone cup. Pressure to the foetal head is applied using four pads projecting forward from the cup's interior. Holding the device by the tube, the user places the cup against the part of the head exposed through the dilated cervix, and presses. This pushes the baby back up into the uterus while releasing any suction pressure that may have been holding it, so allowing the obstetrician to extract it more easily. Because pressure is distributed equally between the four pads with a greater combined surface area than that of a user's fingertips, the risk of inadvertent damage is minimised. The team found some money to employ a product designer who used computer-aided design technology and 3D printing to make a prototype. "We were at the point of getting one made in silicone," says Tydeman, "when we realised that before we started experimenting on women we really ought to test it on a simulator." No such simulator existed – so he decided to make one himself. That Tydeman was able to do this comes as no great surprise once you've glanced at his website. His career may be rooted in medicine but his interests encompass sculpture, furniture making and much else. He works in wood, glass, metals and plastic. "I've got a big workshop with a lathe and a forge," he says. "I make stuff. I always have, ever since I was a child. My dad was a woodwork teacher, my mum was very creative with fabric." Although tests carried out with the Debra prototype showed that the tube would work as intended, Tydeman and his colleagues then faced what he calls a kind of medical catch-22. "We had the tube finished about three years ago… but we were more interested in trying to save lives than selling a product. We thought that the right thing to do before commercialising it was to be sure we'd got the best design." They tried it on a dozen or so women in labour, and concluded that it did what it supposed to. But they held off trying to market it because they wanted to do more extensive, more rigorous clinical studies. This presented a problem. "If you've applied for research money," says Tydeman, "but you've already got what seems to be a commercially viable design, potential funders are going to say that the company aiming to sell it should pay for the work." On the other hand, commercial interest is easier to drum up if you've already got evidence that a device is safe and effective. the head was cast in silicone from a model he'd made in plasticine, and the rest comprised old springs and other bits of stuff lying around his workshop. "It wasn't actually that difficult," Tydeman says. Tydeman can remember the exact moment when the idea of her having a greater role dawned on him. "I was on the sleeper train down from Scotland to London," he says. "Debra was with me because the first Tydeman tube had become available at St Thomas's… It was about midnight, I'd had my free whisky and I suddenly thought, 'Blow me! Even if the tube doesn't work, Debra could be useful as a teaching aid'." With a grant from the Guy's and St Thomas's Charity fund they made Debra more presentable. Tydeman showed the prototype to Adam Rouilly, an established company specialising in medical models and simulators. They were impressed. A year later, the first of Debra's smartened-up sisters was on the market. A proper study of the clinical effectiveness of the Tydeman tube will necessarily involve women giving birth. Assessing the value of Debra as a simulator didn't require human subjects One of the treatments of choice in that era was, naturally, acupuncture. But how to teach tyro-acupuncturists where to place the needles? Simple. A life-size bronze statue dotted with small holes indicated the points of insertion. And how then to test the students' grasp of their subject? If the statute was hollow, filled with liquid and given an outer coating of wax to mask the holes, a correct needle insertion would be followed by a leak. Given the universality of childbirth it's no surprise that, then as now, the womb turns out to be the most simulated of our organs. For the benefit of 18th-century midwives and doctors-in-training, the Bologna surgeon Giovanni Antonio Galli devised a birthing simulator comprising a glass uterus supported by an artificial pelvis and containing a flexible foetus. Trainees had to deliver the baby while wearing a blindfold. Only the tutor could witness the fumbling of their hands. coup de théâtre , this – a facility for exuding suitably coloured liquids at the appropriate moment. Oddly, as medicine became more scientific, most of these devices fell by the wayside. As an academic review of these and other devices has pointed out, much of the 20th century was something of Dark Ages for simulation. Its value in professional training has had to be rediscovered: an endeavour in which inventive people like Graham Tydeman, sometimes with workshops rich in discarded junk, are still fruitfully engaged.

<question>:
What inspired Tydeman to develop his device?

<options>:
A A mannequin
B A sound
C An advertisement
D A smell

<answer>:

B