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 is best indicator of prognosis of soft tissue sarcoma - 
Select and explain. 
A. Tumor size, B. Histological type, C. Nodal metastasis, D. Tumor grade
D: Tumor grade
Answer: D: Tumor grade 
Explanation: Ans. is 'd' ie tumor grade "Histologic grade remains the most impoant prognostic factor for patients with sarcomas."- Schwaz "Sabiston writes - Current staging system for soft tissue sarcoma focus on histological grade of the tumor, size of the primary tumor, and the presence or absence of metastasis. Histologic grade is a major prognostic determinant and is based on degree of mitosis, cellulaity, presence of necrosis, differentiation and stromal content"