Which of the following is an example of an herbivorous fish used for weed control?

Cichlids are recognized as an effective herbivorous fish for aquatic weed control due to their dietary preferences. These fish actively graze on various types of aquatic vegetation, helping to manage and reduce the growth of undesirable plant species in water bodies. Their natural feeding habits contribute to maintaining balanced aquatic ecosystems, making them an excellent choice for biological control of weeds.

Other fish, like goldfish and carp, may influence plant life in water bodies, but they do not primarily consume aquatic vegetation as their main diet. Trout, on the other hand, are predatory fish that mainly feed on smaller fish and insects rather than on aquatic plants. The specific herbivorous nature of cichlids, along with their role in controlling plant growth, distinguishes them as an important species for this purpose.