Answer:
trialability
Step-by-step explanation:
Since in the given situation it is mentioned that an online retailer offers for free try for his customers and the customers select five pairs theywant to try. Also they could select either for purchase or return
So here it related to the trail of its products where the customer could see whether the company product provide the satisfaction or not and according to this they take the decision whether to purchase the product or not
Hence, the last option is correct