With surface temperatures estimated at minus 230 degrees

[14548284]

With surface temperatures estimated at minus 230 degrees Fahrenheit, Jupiter's moon Europa has long been considered far too cold to support life, and with 60 square miles of water thought to be frozen from top to bottom.
A. Europa has long been considered far too cold to support life, and with
B. Europa has long been considered far too cold to support life, its
C. Europa has long been considered as far too cold to support life and has
D. Europa, long considered as far too cold to support life, and its
E. Europa, long considered to be far too cold to support life, and to have

OA is B
can you tell me why A is incorrect?
I think that choice B is run-on

[jeffzolman]

A: Incorrect because of the ", and". The ", and" would indicate a compound sentence and "with 60 square miles of water thought to be frozen from top to bottom" can not stand alone.

Idiom problems...
C. considered as
D. considered as
E. considered to be

[tim]

Jeff took care of most of this for us, so i'll just address the run-on issue:

The best reason B can't be a run-on sentence is because there are NO verbs after the final comma. No verbs means no run-on issue. Thought in this case is being used as a modifier as is frozen; those are the only two candidates that are even close to looking like verbs..

This is a good canonical example to file away, because this construction comes up every once in a while - a possessive introducing a modifying phrase..