How many plant and animal species have been discovered and described so far?
A. 1.5 million
B. 4.5 million
C. 1.5 billion
D. 4.5 billion
Answer:A
How many plant and animal species have been discovered and described so far?
A. 1.5 million B. 4.5 million C. 1.5 billion D. 4.5 billion