Final answer:
Weathering of rocks releases phosphate into the environment, making it available to terrestrial and marine food webs. The correct answer is that weathering is the only way to release phosphorus from rocks.
Step-by-step explanation:
Cause/Effect Relationship of Weathering and the Phosphorus Cycle
The cause/effect relationship between weathering and the phosphorus cycle is that weathering of rocks and volcanic activity releases phosphate into the environment, including soil, water, and air. This release makes phosphorus available to terrestrial food webs. Furthermore, through surface runoff, groundwater flow, and river flow, phosphate enters the oceans where it becomes part of marine food webs. Eventually, some phosphate falls to the ocean floor, contributing to sediment formation.
The correct answer to the student's question is b. Weathering is the only way to release phosphorus from rocks. Weathering does not make phosphorus gaseous, and while it contributes to the transport of phosphorus into the oceans, it's not the process of weathering itself that accomplishes this but the subsequent movement of water. Weathering does not slow down the phosphorus cycle; it is an integral part of the cycle that allows for the continued recycling of phosphate.