$.$ Multinational enterprises $($MNE$)$ may diversify their operations within the host and source countries. Distinguish among these diversification approaches.

a$.(\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_)$ integration generally results in the establishment of foreign subsidiaries that supply inputs going into the finished good.

b$.(\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_)$ integration occurs when the parent firm sets up a subsidiary to produce an identical product overseas.

c$.(\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_)$ integration occurs when the parent firm establishes foreign subsidiaries to produce intermediate goods going into the production of finished goods.

d$.(\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_)$ integration results in a firm's diversification into nonrelated markets.