Which Choice Accurately Conveys the Complexity of Neural Connections in the Human

Which choice accurately conveys the complexity of neural connections in the human brain?

A) About 100 billion neurons each contact 1,000 to 10,000 other neurons.
B) A million or so neurons each contact up to 100 other neurons.
C) 10 million or so neurons each contact up to 10,000 other neurons.
D) A billion or so neurons each contact up to a million other neurons.