This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Surgery
Which of the following type of malignancy is associated with Marjolin's ulcer? 
Select and explain. 
A. Basal cell carcinoma, B. Squamous cell carcinoma, C. Malignant fibrous histiocytoma, D. Neurotrophic malignant melanoma
B: Squamous cell carcinoma
Answer: B: Squamous cell carcinoma 
Explanation: Marjolin's ulcer is an aggressive transformation of a chronic wound in to a malignant lesion. They are usually present in chronic wounds resulting from burns, chronic inflammation or trauma. The most common malignancy found in Marjolin's ulcer is squamous cell carcinoma. Basal cell carcinomas can occur occasionally. Rarely, malignant fibrous histiocytoma, sarcoma and neurotropic malignant melanoma, have also been associated with it. Ref: Schwaz's Principles of Surgery, 9th Edition, Chapter 9; Trends in Bone Cancer Research By E. V. Birch, Volume 24, Page 58; Cancer Symptom Management By Connie Henke Yarbro, 3rd Edition, Page 295; Atlas of Head and Neck Imaging: The Extracranial Head and Neck By Suresh K. Mukherji, Chapter 11.