The following lesion was noticed in a patient with history of involuntary weight loss. What is the diagnosis?

The image shows presence of asymmetric, velvety hyperpigmentation at the back of the neck of the patient suggestive of diagnosis of acanthosis nigricans. It is seen in patients with impaired glucose tolerance and internal malignancy. Choice B is seen in patients with internal malignancy and but has multiple pigmented skin lesions. Choice C is a is a crusty, scaly growth caused by damage from exposure to ultraviolet (UV) radiation. Choice D has red inflamed lesions and is hence ruled out.