The author's attitude towards the possibility of life on the Mars in the future is __. A．doubtful B．positive C．negative D．uninterested

A.doubtful
B.positive
C.negative
D.uninterested

【参考答案】

B
根据全文可以判断，作者对人类在火星上生存的可能性抱着积极、乐观的态度。