Answer:
Options A and D are correct:
- Glacier movement over the crust
- Trapped acidic water dissolving large amounts of limestone
Step-by-step explanation:
Glacial lakes: It has been well reported that glacial erosion often leads to the development of lakes. When a glacier moves, it erodes the sediments which lead to the formation of depressions. In later years, these depressions are filled with water and form a lake. This is why these lakes are recognized as "glacial lakes".
Lakes formed by dissolving limestone: We know that acids can dissolve the limestone (CaCO3) very quickly. Therefore, if acidic water traps in an area where the bed-rock is made up of limestone, the water will dissolve it and form a depression. The acidic water could stay the same place forming acidic lakes or could be replaced with normal water later on due to hydrogeological processes.