Final answer:
The Plow pose is a controversial upper-body yoga stretch that can be risky for injury if proper caution is not taken.
Step-by-step explanation:
The upper-body yoga stretch that is considered controversial and may be a risk for injury is the Plow pose (option c).
In the Plow pose, the person is supine with upper limbs, including palms, touching sides and lower limbs touching at sides. This pose involves flexing the spine and bringing the legs over the head, which can put strain on the neck and spine. There is a risk of injury if proper alignment and caution are not maintained.
It is important to listen to your body and work within your own limits. If you feel any discomfort or pain, it is advisable to modify or skip this pose and consult with a yoga instructor or healthcare professional.