<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 32-year-old woman comes to her physician because of increasing back pain for the past 10 months. The pain is worse in the morning when she wakes up and improves with activity. She used to practice yoga, but stopped 5 months ago as bending forward became increasingly difficult. She has also had bilateral hip pain for the past 4 months. She has not had any change in urination. She has celiac disease and eats a gluten-free diet. Her temperature is 37.1C 98.8F, pulse is 65min, respirations are 13min, and blood pressure is 11672 mmHg. Examination shows the range of spinal flexion is limited. Flexion, abduction, and external rotation of bilateral hips produces pain. An x-ray of her pelvis is shown. Further evaluation of this patient is likely to show which of the following?? A: High levels of rheumatoid factor, B: HLA-B27 positive genotype, C: Presence of anti-dsDNA antibodies, D: High levels of creatine phosphokinase, E: Presence of anti-Ro and anti-La antibodies,  <response>: This is a clinical vignette describing a 32-year-old woman with chronic back pain worse in the morning and improving with activity, as well as bilateral hip pain. She has a history of celiac disease. On exam she has limited spinal flexion and pain with range of motion of the hips. An x-ray shows sacroiliitis. The key findings are inflammatory back pain worse in the morning, bilateral hip pain, limited spinal flexion, and sacroiliitis on x-ray. This clinical presentation is most consistent with ankylosing spondylitis, a type of inflammatory arthritis that primarily affects the spine and sacroiliac joints. The correct answer is therefore likely to be HLA-B27 positive genotype, as HLA-B27 is associated with susceptibility to ankylosing spondylitis. Rheumatoid factor, anti-dsDNA antibodies, and anti-RoLa antibodies would indicate other types of autoimmune disease not consistent with the presentation. Creatine phosphokinase levels would not be relevant.B: HLA-B27 positive genotype 