Option (c)

Option (a) is wrong because of this line in the passage "Kelly finds reassurance in Hilary Putnam's recent re-thinking of philosophical realism"
Option (b) is wrong because of this line in the passage "This is partly the issue that Thomas Pfau takes up polemically". This indicates that some people/authors were against Pfau's thoughts.
Option (c) does not find support in the passage. Look at the line "But still more questions arise. Does the potential solipsism necessarily inherent in any aesthetic pleasure find a rapport, or a reciprocal production of meaning, with the empirical world? If Romanticism has a grasp  upon the actual that is not merely weak, how do the actual and the pleasure of that aesthetic "grasp" signify to each other?" It looks as if the author doesn’t fully agree with Kelly's thoughts.