I have a question about a practice test!! Why is the correct answer C? I chose D.

Question

The panspermia hypothesis eventually fell out of favor for a variety of reasons.[A] Skeptics pointed out that microorganisms could not possibly survive the damage caused by ultraviolet radiation and cosmic rays while being propelled out of a solar system away from a star. Indeed. it was unclear how biological material could escape from a planet by natural processes in the first place. [B] If unprotected, the molecules of life would quickly be destroyed by radiation near the ejecting planet. [C] Furthermore, it was not clear how microorganisms, having made a journey across the huge distances of interstellar space, could have safely descended to the surface of the Earth or any other planet. [D]Arrhenius himself argued that organisms caught inside meteorites would be subjected to incandescent* temperatures while entering the atmosphere of a terrestrial body. Such heat would destroy any life-forms lucky enough to have survived to this point.

 

Look at the four squares [   ] that indicate where the following sentence could be added to the passage.

 

However, even if organisms were somehow shielded inside fine grains of carbon they would be too heavy to be ejected from a planetary system by the pressure of radiation.

Answer 1

At first glance, the answer could be either [B] or [C].  However, insert the sentence in either of those two places and read the passage out loud.  Look for a common subject, key word or phrase.  The sentence in question actually only has something in common with the sentence, "If unprotected, the molecules of life would quickly be destroyed by radiation near the ejecting planet."  The sentence does not have anything in common with the sentence that comes before [D], even though it follows a logical thought-pattern.

The key phrase here is "ejecting planet", so it makes the most sense to insert the sentence at [C]. 

 

Note:  It's crucial to read this these kinds of questions out loud and highlight (or pay close attention to) any common subject, phrases, and key words.  That's the best way to get the right answer.