Answer: 4. Penetration
Explanation:
Penetration strategy is known as a strategy which is used by companies in the market to convince and entice customers to buy their new good or product. The company introduces their new product to the market by making the price of the good to be as low as possible in order for customers to identify and buy the product instead of buying other companies products. Thus, this leads to increase in the purchase of the product because consumers tend to buy more goods with low prices and the company's market share in the market also increases.