Often considered a precursor to modern existentialism, Kierkegaard's philosophical writings explore the individual's profound freedom and the burden of choice, concepts which have profoundly influenced subsequent thinkers.
Correct: C
The opening modifier 'Often considered a precursor to modern existentialism' must logically modify a person, Kierkegaard, not 'Kierkegaard's philosophical writings.' Options A, B, and D fail to correct this dangling modifier. Options C and E correctly place Kierkegaard as the subject. The clause 'concepts which have profoundly influenced subsequent thinkers' is a restrictive clause, meaning it provides essential information to identify *which* concepts are being discussed, so 'that' is preferred over 'which.' This eliminates the 'which' in options A. Between C and E, option C uses 'explored' (past tense), which is more appropriate as Kierkegaard's writings and their initial exploration of these concepts occurred in the past, leading to a long-term influence. Option E uses the present tense 'explores' and a participial phrase 'profoundly influencing' which is less precise than a full clause for conveying the historical influence of specific concepts. Therefore, option C is the best choice for fixing the modifier, using the correct relative pronoun, and maintaining appropriate tense.