The correct answer is - D. use a greenhouse.
If the climate is not suitable for a certain exotic plant, and the reason for that is that it is colder than the place from where the plant originates, than the best solution is to plant it in a greenhouse.
The greenhouse will provide higher temperature for the plant throughout the whole year, so it is will have a proper temperature, similar to the one it is adapted to. Also, it will receive sufficient amounts of light. It will be protected from the outside influences such as the cold winds, snow, low temperatures, so it will have a good chance of growing.