What is the estimated number of extant species on Earth? A) 1,000 ...

[penza]

What is the estimated number of extant species on Earth?
A) 1,000 to 50,000
B) 50,000 to 150,000
C) 500,000 to 1,000,000
D) 10,000,000 to 100,000,000
E) 5 billion to 10 billion

[plus1]

I recall doing this last year, it's D, bye bye!

[penza]

Thanks so much!