Correct Answer - Option 2 : Both Statement (I) and Statement (II) are individually true but Statement (II) is not the correct explanation of Statement (I)
Crawler excavators are used in hilly areas where risks of sliding of machinery are on the verge. Since, they are used in hilly areas and bulky in size, hence moved at slow speeds.
It has low ground pressure because of spreading of load on large area. Therefore, it is also used where soil support is weak or soft grounds.
Other type of excavators
1. Wheel Excavators: They are only used for plain ground operations. Because of wheel, it is not suitable for hilly areas due to low grip value to the ground.
2. Long reach Excavator: It has long arm and hence, can be able to reach the top of buildings.
3. Drag Line Excavators: They are used for civil engineering operation on roads, port construction etc.
4. Suction Excavators: They are used to safely identifying and removing underground elements.