which processes form glaciers?\nimpact and deflation\nplucking and abrasion\ndeposition and…

Brief Explanations:

Glaciers form when snow accumulates over time and is compacted into ice. Impact and deflation are related to wind - driven processes in deserts. Plucking and abrasion are glacial erosion processes. Deposition and erosion are general geological processes not specific to glacier formation. Accumulation of snow and its compaction are the key processes in glacier formation.

Answer:

accumulation and compaction