Which of the following is not a reason why business combinations occur?

a.,Vertical integration - one firm's output is another firm's distribution or further processing

b.Quick entry for new and existing products into the marketplace

cHorizontal integration - two companies that produce the same types of products combine to expand their product portfolio

d.Expanding the size of a company to improve its economies of scale allowing greater efficiency and negotiating power

e. All of the above are correct