Choose the word that is most suitable to fill the numbered gap in the passage.
Locusts have from time to time been the cause of terrible __76__ of farms. __77__ of locusts can, in a few hours strip vast areas of green and fertile country of all signs of __78__. They are __79__ or periodic __80___ after a heavy __81___ of an area, they may not appear for ten years or fourteen years. Now that more is known of the way of life of locusts, these periodic __82___ are better under stood and consequently more __83___ scientist know the regions in which the gregarious phrases of locusts may occur and can even sometimes __84__ when an__85___can take place.
A. Deprivation B. Infection C. Disease D. Devastation
