SAT Question 166efaa2: Form Structure And Sense answer and explanation

English - Form Structure And Sense - Pronoun Antecedent Agreement
0:00
FREE OFFICIAL BANK
Public-awareness campaigns about the need to reduce single-use plastics can be successful, says researcher Kim Borg of Monash University in Australia, when these campaigns give consumers a choice: for example, Japan achieved a 40 percent reduction in plastic-bag use after cashiers were instructed to ask customers whether ______ wanted a bag.
14
Difficulty:Easy
Which choice completes the text so that it conforms to the conventions of Standard English?