Final answer:
The young man's symptoms of muscle weakness and rash could indicate an autoimmune condition like dermatomyositis or systemic lupus erythematosus (SLE), requiring testing for autoantibodies and muscle enzymes.
Step-by-step explanation:
A young man presenting with progressive proximal muscle weakness, generalized fatigue, and a red nonpruritic rash on the face and body, especially around the knees and elbows, should have a workup that includes screening for autoimmune diseases and connective tissue disorders. The combination of muscle weakness and characteristic rash, particularly if worsened with sunlight, may lead to a suspicion of conditions such as dermatomyositis or systemic lupus erythematosus (SLE). These conditions are known to cause muscle inflammation and skin manifestations, and can be confirmed through blood tests for autoantibodies, muscle enzyme levels, and possibly a muscle biopsy.
The best answer to the provided question is autoimmune screening rather than screening for options A (Carcinoma), B (Heart disease), C (Intestinal bleeding), D (Fibrotic lung disease), or E (Stroke), which are less consistent with the given symptoms.