Modem bourgeois society, said Nietzsche, was decadent and enfeebled "” a victim of the excessive development of the rational faculties at the expense of will and instinct. Against the liberal-rationalist stress on the intellect, Nietzsche urged recognition of the dark mysterious world of instinctual desires "” the true forces of life. Smother the will with excessive intellectualizing and you destroy the spontaneity that sparks cultural creativity and ignites a zest for living. The critical and theoretical outlook destroyed the creative instincts. For man's manifold potential to be realized, he must forego relying on the intellect and nurture again the instinctual roots of human existence
(d) is the most appropriate and precise way to explain the passage. From the third sentence it is clear that excessive intellectualizing destroys creativity and the last line of the paragraph says that human beings should nurture their creative instincts. On the whole, the paragraph puts the blame on excessive rational thinking responsible for the decline of the modern society. While option (a) misses the point of critiquing modern society, (b) misses Nietzsche's advice to nurture creative instincts