Final answer:
The poetic form inspired by Japanese poetry but not part of its traditional literary forms is the cinquain.
Step-by-step explanation:
The form of poetry that was inspired by Japanese poetry but was never part of that culture's literary tradition is B) cinquain. Unlike haiku and tanka, which are traditional Japanese poetic forms, cinquain is an American invention that has similarities to Japanese poetry in its conciseness and focus on imagery, but it does not originate from that culture. The Japanese forms such as haiku, with a 5-7-5 syllable count, and tanka (or Waka), with a 5-7-5-7-7 syllable count, are deeply embedded in Japanese literary tradition, as are other forms like renku and katauta. The development of these forms coincided with cultural growth and the invention of Japanese scripts like Katakana and Hiragana during periods such as Heian.