Correct option is B
Tiger prawn (Penaeus monodon) is the highest priority brackish water fish due to its high growth rate and tolerance to temperature fluctuations. This species is commercially significant in aquaculture for its rapid growth, adaptability to varying environmental conditions, and overall hardiness. Tiger prawns are well-suited for cultivation in brackish water, which is a mix of saltwater and freshwater. Their ability to tolerate fluctuations in temperature makes them resilient to changes in environmental conditions, contributing to their suitability for aquaculture.