By default yes — a 48 kHz audio track in MOV becomes 48 kHz in MP2. If you need 44.1 kHz (CD-quality) for compatibility with older players, the advanced options include a sample-rate dropdown.
Audio extraction is much faster than video re-encoding — typically 5-15% of the source duration. A 1-hour MOV → MP2 finishes in 3-9 minutes on the standard pipeline.