The correct answer is D) increase holding power. Increasing the area of the anchor flukes (the curved parts of the anchor that dig into the seafloor) will increase the anchor's holding power. This is because a larger fluke area creates more surface area in contact with the seabed, which allows the anchor to grip the bottom more effectively and resist being pulled out by the force of the boat. The larger flukes also enable the anchor to penetrate the seafloor more completely, further enhancing its holding capability. The other answer choices are incorrect because: A) increasing the fluke area does affect holding power, B) it increases rather than decreases holding power, and C) while increased penetration is part of the reason, the key factor is the increased surface area and grip on the seafloor.