Final answer:
The sales associate should politely ask the customer with the child to finish the ice cream outside the store, as it is important to address the situation with professionalism and adherence to the store's policy.
Step-by-step explanation:
The best response for the sales associate when seeing a customer's child eating an ice cream cone in front of new laptops, despite a store policy of 'No food or drink to be brought into the store', would be to take a professional yet gentle approach. Given the options provided, the most appropriate action would be to politely ask the customer with the child to finish the ice cream outside the store.
Confronting such a situation with courtesy and respect for the customer is key to maintaining a good store atmosphere while also upholding the store's policy. Additionally, by handling the situation directly and diplomatically, the sales associate prevents any accidents and ensures a clean environment for both the merchandise and other customers. If the customer is uncooperative, then calling for managerial assistance would be an appropriate next step to resolve the issue.