题目选项分析

Relying exclusively on radio communication, both to transmit messages it has encoded and to receive messages, SETI is the most heavily funded project of its kind, yet the search for extraterrestrial life will likely be stymied if this form of communication does not yield any tangible breakthroughs.

Relying exclusively on radio communication, both to transmit messages it has encoded and to receive messages, SETI has been the most heavily funded project of this kind, yet the search for extraterrestrial life would likely have been stymied if this form of communication does not yield any tangible breakthroughs.