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: Physiology
Fine, irregular contraction of individual fibers is called: 
Select and explain. 
A. Fasciculations, B. Fibrillation, C. Tics, D. Spasm
B: Fibrillation
Answer: B: Fibrillation 
Explanation: Fine, irregular contractions of individual fibers is known as fibrillations. This is the classic picture of a lower motor neuron lesion. If the motor nerve regenerates, the fibrillations disappear.  Usually,  the contractions are not visible grossly, and they should not be confused with fasciculations, which are jerky, visible contractions of groups of muscle fibers that occur as a result of pathologic discharge of spinal motor neurons.