Markets are so dynamic, therefore, prices should be adapted to the fast changing environment. There are many price-adjustment strategies including dynamic pricing, psychological pricing, discount and allowance pricing, segmented pricing, geographical pricing, promotional pricing, and international pricing. In dynamic pricing, prices are being adjusted continually to maximize revenue. For example, prices are changing thousands times a day in the airline sector. In psychological pricing, prices are adjusted based on a psychological viewpoint rather than eceonomic perspective. For example, companies consider price thresholds in consumers’ mind while changing prices for products. Discount and allowance pricing refers to a reduction in the price of the products for consumers who buy large quantities or pay early. In segmented pricing, prices are differentiated based on customer, location, or product rather than cost. For example, although cost of providing a hotel room does not change, rooms with a sea view are more expensive than the rooms without a good scenery. Geographical pricing refers to setting prices for customers who are in different locations in order to cover high shipping costs. For instance, lower prices are charged for customers who are close to oil refinery while higher prices are charged for ones who are far away. Promotional pricing means reducing prices for a while to increase short term sales. The prices are set below list price. International pricing refers to setting prices for different countries. For example, a company may charge different prices for different countries, or it may set a fixed price for every country. Therefore, the correct option is A.