Isay that even their exceeding density did not prevent our perceiving this -- yet we had no glimpse of the moon or stars -- nor was there any flashing forth of the lightning. but the under surfaces of the huge masses of agitated vapour, as well as all terrestrial objects immediately around us, were glowing in the unnatural light of a faintly luminous and distinctly visible gaseous exhalation which hung about and enshrouded the mansion. which statement best describes the effect of the narration on the story? the narration suggests a supernatural presence at the dwelling. the narration suggests a scientific phenomenon is occurring. the narration suggests a surprising change in the weather pattern. the narration suggests an approaching sunrise.

A. The narration suggests a supernatural presence at the dwelling.   

Let me state it in a simpler form. 

"There was no glimpse of the moon or stars nor was there any flash of lightning but the under surfaces and terrestrial objects surrounded them, glowing in the unnatural light of a faintly luminous gas." 
If you try to interpret this statement, it seems likes there's an alien invasion. The world itself "unnatural" could fairly relate to "supernatural". 

Supernatural phenomena can never be explained by science, therefore, this can't be a scientific phenomenon. 

A surprising change in the weather and an approaching sunrise are both scientific phenomena since these can be explained by science.
Note: "Approaching sunrise is a natural light". It obviously contradicts the statement. 
A flash of lighting is one of the manifestations of a surprising change in the weather but the statement above mentioned otherwise. 

Sure but what’s your question?