What defines tactile inspection in underwater scenarios?

Answer: B — Examines materials by touch when visibility is low

Tactile inspection in underwater scenarios is defined primarily by the method of examining materials through touch, particularly in situations where visibility is severely limited. This approach is essential in underwater environments, where factors like murky water, silt, or other visual obstructions can make it difficult or impossible to see physical structures clearly. By relying on physical contact, inspectors can gather critical information about a structure's condition that visual inspections might miss, such as surface textures, material integrity, and any potential deformities or damages. This tactile method is particularly beneficial in assessing the condition of submerged components like bridge piers and foundations, where visibility is compromised. It allows inspectors to obtain a more complete understanding of structural health, which is crucial for effective maintenance and safety evaluations of underwater infrastructure.