What is included in the main cabin of the CRJ 700 with 70 passengers?

The correct choice reflects the configuration of the CRJ 700 aircraft, which typically comprises a mix of different seating classes. In this case, the aircraft is designed to accommodate 70 passengers, and the main cabin consists primarily of economy class seating.

In the CRJ 700, the layout includes a total of 70 seats, where a significant portion is allocated to economy class, specifically 48 seats in this configuration. This setup allows for a balance between comfort and capacity while maximizing the number of passengers that can be accommodated in the main cabin.

The other options do not accurately represent the seat distribution or conflict with standard configurations for this model. For example, while Delta+ seats may exist in some configurations, they do not make up a significant number of seats to reach the total passenger count specified. Similarly, a much higher number of first-class seats or alternative arrangements would not align with the standard layout of the CRJ 700. Therefore, the main cabin's seating configuration, which includes 48 economy seats, is indeed the most accurate representation.