Metastatic breast cancer
Answer : D Dermatomyositis
Dermatomyositis is an immune mediated disorder that occurs as a paraneoplastic syndrome in 15 percent of cases.
Common malignancies associated with dermatomyositis include lung cancer, ovarian cancer, breast cancer, and some gastrointestinal tumors.
Cerebral metastases and PML would be less likely to cause symmetric weakness.
Myasthenia Gravis is a neuromuscular junction disorder which would be less common.