My answer B
A) This takes the conclusion too far since nothing is mentioned about other agents or adjacent land owners.
C) Again nothing is mentioned about new young families coming and buying land due to bargain. Not right
D) This may be right since if town council does not appeal for commercial development for < 5K ares area, the real estate agent cant do anything. But there 2 faults, the town council is asked to reconsider, it is not said to reject or take back their appeal. Another, nowhere it is mentioned that if the airport is not built, land prices in the area will rise.
E) Irrelevant
Only B states that even though county town council is a general body, it is not supporting financial interest of residents. Which seems relevant to the passage and no extra info is added.