Select the most appropriate option that can substitute the highlighted segment in the given sentence. If there is no need to substitute it, select ‘No substitution’.
Solomon always refers in the dictionary for clearing doubts about words.

Correct option is C

The most appropriate option to substitute the highlighted segment in the given sentence is (c) "to the dictionary."
 The sentence means that Solomon consults the dictionary to clear his doubts about words, so the preposition "to" indicates the direction of this action.
 Therefore, the correct sentence would be "Solomon always refers to the dictionary for clearing doubts about words."