Nolutin, a new, effective heart medicine, is manufactured using oil that is obtained from a rare variety of fish called Orintok, increasing the demand for this fish. With the latest innovation in technology, Orintok can now easily be farmed if the required environmental conditions are maintained, including a set water temperature and a constant replacement of fresh water in the tanks. In fact, looking at the increased demand for this high priced fish, many fish farmers who were earlier farming Astintok fish are now planning to farm Orintok.

Which of the following, if true, provides the best reason that the increased demand for the fish is not temporary?

A) The demand for Astintok has been on the rise for the past few years and might slightly rise this year as well.
B) A synthesized, inexpensive substitute for the fish oil obtained from Orintok has not been well received in the market.
C) If most Astintok farmers choose to farm only Orintok then the supply of the fish will significantly exceed the demand for the fish.
D) Tountin, another new medicine, is also manufactured using the oil from Orintok.
E) Some physicians do not prefer prescribing Nolutin to patients because taking this medicine can slightly increase the risk of high blood pressure.

Please provide detailed explanations -- especially for B and D.