The correct option is
B Carnivorous
Praying mantis is carnivorous, eating mainly insects and other small animals. In addition to insects such as crickets and grasshoppers, spiders etc. Gardeners who prefer to avoid pesticides may encourage mantises in the hope of controlling insect pests. However, mantises do not have key attributes of biological pest control agents; they do not specialize in a single pest insect, and do not multiply rapidly in response to an increase in such a prey species, but are a general predator. They eat whatever they can catch, including both harmful and beneficial insects. They, therefore, have "negligible value" in biological control.
So, the correct answer is (B)