Identify the appropriate direct speech form of the following sentence:
He greeted me and asked where I was going.
1. He asks, "Hello, where are you going?"
2. He asked, "Hello, where you are going?"
3. He said, "Hello, where you are going.."
4. He said, "Hello! Where are you going?"

Option A: In this sentence, the word 'Hello' should be followed by an exclamation mark since it is used to attract someone's attention. This statement is grammatically wrong.

Option B: In direct speech, when we report someone's words, we should maintain the correct verb tense and word order. In this case, the reported question "Where you are going" should follow the standard subject-verb order, which is "Where are you going?"

Thus, this statement is also grammatically wrong.

Option C: As the question asked is not followed by a question mark, this statement is not correct.

Option D: Since this statement is grammatically correct and represents the exact words spoken by someone, this is the correct option.

The correct option is D.