Cleavage is a mode of folding: 
1) It is a process where in all internal movements are along shear planes which do not change their position during the entire process. 
2) it is a process wherein all internal movements are along shear planes which change their position during the process. 
3) The process involves dilation in the vertical direction. 
4) The process involves compression in a lateral direction. 
Which of the above statements are correct?