A key strategy in sustainable farming is integrated pest management (IPM) which is the combination of different techniques to create an effective pest control system. Not all pests need to be eliminated; monitoring and prevention of pest is also an integral part of IPM.

Aquafarming is the farming of aquatic species such as fish, crustaceans, mollusks, and aquatic plants and often uses sustainable farming techniques. The limits of a certain type of aquafarming pest during the farming of catfish might be expressed as a 10 ug/L, not to exceed 2 days, and not to recur more than once every 6 months.

What does 6 months represent in the management of pest limits for the above example?

A)

average

B)

duration

C)

frequency

D)

magnitude