TASK DEFINITION: In this task, find the most appropriate number to replace the blank (indicated with _ ) and express it in words.
PROBLEM: Rheas are brownish instead of black like the ostrich and have _ toes instead of two.

SOLUTION: three

PROBLEM: People have _ kidneys.

SOLUTION: two

PROBLEM: Human malaria is caused by _ species of Plasmodium . .

SOLUTION:
four