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: Anatomy
Flexion of MCP joint and extension of IP joints is the major action of ? 
Select and explain. 
A. Palmar interossei, B. Dorsal interossei, C. Lumbricals, D. FDS
C: Lumbricals
Answer: C: Lumbricals 
Explanation: Ans. is 'c' i.e., LumbricalsAmongs the given options three muscles cause flexion of MCP joint and extension of IP joint.LumbricalsPalmar interosseiDorsal interosseiBut these movements are mainly produced by lumbricals. Palmar and dorsal interossei assist the lumbricals for these movements.Their major action is :?Palmar interossei -4 Adduction of fingersDorsal interossei - Abduction of fingers