Blaze Scooters is a manufacturer of electric scooters. Warranty expenses have been increasing for each quarter in the last fiscal year. The descriptive question is "Which electric scooter models contributed to the increased warranty expenses?" What measures can be used to answer the question?

Group of answer choices

a$.$ The total sales for each scooter model

b$.$ The projected warranty expense for each model for the next fiscal year

c$.$ The percentage of products returned for repairs for each scooter model

d$.$ The percentage change of labor costs compared with the prior quarter