The correct answer is option 'A' - "did you not throw". Let's break down the sentence and analyze each option to understand why this is the correct choice.

The sentence is in the past tense and is asking about the reason for not throwing the bag away. Let's analyze each option:

a) did you not throw - This option uses the correct verb tense and forms a question in the past tense by using the auxiliary verb "did" with the subject "you" and the base form of the verb "throw". This is the correct choice because it forms a grammatically correct question in the past tense.

b) had you not threw - This option is incorrect because it uses the past participle form "threw" instead of the base form "throw" after the auxiliary verb "had". When forming a question in the past tense, we use the auxiliary verb "did" followed by the base form of the verb.

c) did you not thrown - This option is incorrect because it uses the past participle form "thrown" instead of the base form "throw" after the auxiliary verb "did". When forming a question in the past tense, we use the auxiliary verb "did" followed by the base form of the verb.

d) you did not thrown - This option is incorrect because it uses the past participle form "thrown" instead of the base form "throw" after the subject "you". In this sentence, we need to use the base form of the verb "throw" to form a grammatically correct sentence.

e) No correction required - This option is incorrect because the original sentence is grammatically incorrect. The correct form should be "did you not throw" to form a question in the past tense.

In conclusion, the correct answer is option 'A' - "did you not throw" because it uses the correct verb tense and forms a grammatically correct question in the past tense.