Read the short paragraph below. It is from a student research paper on red kangaroos.
(1) The red kangaroo is a really cool animal that's lots of fun to learn about. (2) Found in Australia, the red kangaroo is a mammal that weighs about 200 pounds on average. (3) As you'd maybe expect, girl roos are smaller than boys. (4) The red kangaroo has super strong back legs. (5) It can travel at speeds that exceed 35 miles per hour. (6) When red kangaroos are born, they complete their development inside the pouch of the female.
Which sentence uses a formal tone that is appropriate for academic writing?
A.
sentence 1
B.
sentence 2
C.
sentence 3
D.
sentence 4