Explanation

B is likely correct as Surah Al-A'raf has 31 verses (Ayat), and the number of Rukus often corresponds closely to or is cited as a specific count near the actual verse count. A is incorrect because it does not match the commonly accepted count for this Surah. C is incorrect because it is an arbitrary number that does not reflect the structure of the Surah. D is incorrect because there is a generally accepted numerical answer.