Each of the Following Groups of Things Has Been Divided

Short Answer

Each of the following groups of things has been divided according to a single basis of classification. However, one item in each group does not belong; it does not fit that single basis of classification. Read each group of items carefully; then select the letter of the one item that does not belong. Next, select the single basis of classification that includes the rest of the group.
Part A: Apartments
a. two-bedroom
b. three-bedroom
c. penthouse
d. studio apartment
Part B: Basis of classification:
a. location in the building
b. number of bedrooms
c. cost of rent