A company has installed a new 802.11g point-to-point connection between two buildings and isexperiencing low throughput across the link. The current setup involves a wireless bridge on the roof with an omni-directional antenna. Which of the following would BEST improve the link performance?（）

A. Replace the wireless bridges with wireless access points.
B. Install bi-directional amplifiers at both sites.
C. Configure channel hopping on both wireless bridges.
D. Replace the omni-directional antennas with Yagi antennas