Bunuel
12 Days of Christmas 🎅 GMAT Competition with Lots of Questions & FunBitter crab disease is a parasitic infection that poses a significant danger to crustacean fisheries, since infected crabs
were observed to have increased mortality rates as high as 86 percent.
(A) were observed to have increased mortality rates
(B) were observed to have increasing mortality rates
(C) have been observed to have increased mortality rates
(D) had been observed to have increased mortality rates
(E) have been observed to have increasing mortality rates
Bitter crab disease is a parasitic infection that poses a significant danger to crustacean fisheries, since infected crabs were observed to have increased mortality rates as high as 86 percent.
(A) were observed to have increased mortality rates
(B) were observed to have increasing mortality rates
(C) have been observed to have increased mortality rates
(D) had been observed to have increased mortality rates
(E) have been observed to have increasing mortality rates
Increasing vs Increased
(A) were observed to have increased mortality rates
-- 'were observed' refers to an action in the past. Incorrect usage here
(B) were observed to have increasing mortality rates
-- incorrect use of 'increasing'
(C) have been observed to have increased mortality rates
-- correct usage(D) had been observed to have increased mortality rates
-- 'had been' is incorrect tense usage here
(E) have been observed to have increasing mortality rates
-- incorrect use of 'increasing'
Option C