In a booking record, how can you calculate the difference in days between the order...

Comprehensive and Detailed Explanation From Exact Extract:

In ABAP, when calculating the difference between two date fields (type DATS), the result is directly a type i (integer) representing the difference in days.

Statement B is correct:

data(gv_diff_days) = gs_booking-flight_date - gs_booking-order_date.

This directly subtracts two DATS fields, resulting in an integer value for the number of days difference. No conversion is necessary.

Statements A and D are incorrect because the conv d( ... ) attempts to convert the result back to a DATS type, which is invalid since the result is an integer (number of days), not a date.

Statement C is syntactically correct but would produce the negative of the desired value (flight date - order date). It is semantically incorrect for the use case.

This approach is consistent with ABAP for Cloud Development, which requires explicit typing, and ABAP language version strict mode, where automatic type inference is restricted.