This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Upper Extremity, Subject name: Anatomy
Medial border of cubital fossa is formed by: 
Select and explain. 
A. Brachioradialis, B. Pronator teres, C. Biceps brachii, D. Brachialis
B: Pronator teres
Answer: B: Pronator teres 
Explanation: Ans. B. Pronator teresThe cubital fossa is the triangular area on the anterior view of the elbow.Boundaries-a. Superior boundary -- an imaginary horizontal line connecting the medial epicondyle of the humerus to the lateral epicondyle of the humerusb. medial (ulnar) boundary -- lateral border of Pronator Teres muscle originating from the medial epicondyle of the humerus.c. lateral (radial) boundary -- medial border of Brachioradialis muscle originating from the lateral supraepicondylar ridge of the humerus.d. apex- it is directed interiorly, and is formed by the meeting point of the lateral and medial boundaries