Final answer:
Bonnie will list a total of 1,425 square feet, combining the upper level of 450 square feet with 975 square feet from the main floor after subtracting the unfinished laundry area. However, this calculation does not match any of the options provided in the question. The closest matched option is D (1,650 square feet), but it improperly includes the basement area, which goes against the given MLS system rules.
Step-by-step explanation:
The square footage that Bonnie will mention in her MLS listing and marketing materials is the sum of the upper level and the main floor excluding the unfinished laundry area. The upper level is 450 square feet. The main floor square footage, once the unfinished laundry area of 225 square feet is subtracted from 1,200 square feet, equals 975 square feet. Since the MLS system disregards below-grade square footage, the finished basement is not included in the square footage calculation. Therefore, the total square footage to be mentioned in the listing is the addition of the upper level and the adjusted main floor, which is 450 + 975 = 1,425 square feet. However, this is not an option provided in the question. It seems there might be an error in the question as none of the options correctly matches the calculation. The closest correct answer based on the options given is 1,650 square feet (Option D), but it incorrectly includes the basement square footage which should be disregarded according to the provided MLS system rules.