Market Penetration is a strategy for company growth by increasing sales of current products to current market segments without changing the product. 

Product development is a strategy for company growth by offering modified or new products to current market segments. 

Diversification is a strategy for a company’s growth through starting up or acquiring businesses outside the company’s current products and markets. 

Downsizing is reducing the business protfolio by eliminating products of business units that are not profitable or no longer fit the company’s overall strategy. 

Therefore, the answer is "B".