Answer: I believe the answer to be indeed the second option, "radiant, and seductive".
Explanation:
When listing things, actions, ideas etc., it's more common to use words belonging to the same category (nouns, adjectives, adverbs and so on). It not only sounds better, but it also seems to make more logical sense as opposed to the breaking of the sentence's rhythm by using a word that belongs to a different class.
Such breaking is precisely what happens if we don't change anything in the sentence "<em>From April to the hot season again, it is </em><em>blossoming, radiant, and a seductress</em><em>." </em> The structure of the listing portion is adjective, adjective, noun. If, however, we use the adjective "seductive" instead of the noun "seductress", we have what we call parallelism. The listing sounds better, the words seem to have the same importance and to follow a certain pattern.
