IMO OA should be C

The author is claiming that the 'Social Promotion' policy is flawed since it allows schools to promote students based on the results of a standardized test and it doesn't consider whether a student has passed an English class.

So schools might be testing English proficiency in the standardized test as well (hence no need to give weightage to English Class pass/fail).

A) Do students have the option of taking a standardized test in a language other than English?...................Trap answer. it doesn't talk about whether Standardised Test tests English proficiency as well that can give some indication to schools whether to promote a student or not.

B) What is the rate of graduation from schools at which social promotion" is commonly practiced?.......................Not relevent

C) How rigorous are the questions on these standardized tests that pertain to English skills?..................Looks fine. If questions are not that tough then most of the students would pass the test and promote to the next class.

D) How prevalent is “social promotion" among school districts in more suburban areas?..................Irrelevant

E) If a student fails a standardized test, is he or she given the chance to take it again before having to be kept back?.............Irrelevant