Final answer:
Expansion selling encompasses techniques such as cross-selling, reselling, partial-line selling, and repeat buy.
Step-by-step explanation:
Expansion selling refers to the strategy of offering additional products or services to existing customers. It encompasses various techniques such as cross-selling, reselling, and partial-line selling. Cross-selling involves recommending related products that complement or enhance the customer's original purchase. Reselling refers to selling the same product to a customer who has previously bought it. Partial-line selling involves offering a limited range of products or services to complement the customer's initial purchase. Repeat buy refers to customers making multiple purchases from the same seller.