4.1.1 However, [when we look at（观察）the 100 billion stars (恒星）in our galaxy(银河)(the Milky Way),and 100billion galaxies（星系） in the observable Universe（可见宇宙）], it seems inconceivable(难以置信的)that at least one of these planets does not have a life form on it; [in fact], the best educated guess（最有根据的推测） (we can make)， [using the little (that we do know about the conditions for carbon-based life(碳基生命)) ], leads us to estimate that perhaps one in 100,000 stars(恒星） might have a life-bearing planet （孕育生命的行星）(orbiting it).Which of the following is the right description to the logical connection of the semicolon （分号） in the above-mentioned sentence?

A. The semicolon is used to join two coordinating clauses.
B. The semicolon is used to separate the long sentence into two independent clauses.
C. The semicolon is used to explain the reasons.
D. There is no logical connection used here.