I agree with what Mike Kozar said. This usage is extremely informal. In a neutral register, one might say "She has something like ten cars" to mean the same thing.

@SovereignSun That is correct in non-rhotic dialects of English.

No, it's essentially asking what a man's conscience is for if he doesn't use it. If you know a place to ask this question, it might be good to have someone translate the passage into your language for you.

It means "to any degree at all," "at all," "to any extent." The word "least" means "smallest" here.

No, there's no conflict. For example, you can say "Have you ever listened to that radio program, even for a minute?"

It sounds like the kind of thing a native speaker might say speaking spontaneously. But "wait to book the flight" or "wait before booking the flight" sound better, and would probably be preferred by someone giving thought to what they were saying.

Choices 1, 4 and 5 are all okay. They all mean the same thing. Choice 1 would be preferred if there was some reason to draw attention to the contrast right at the beginning of the sentence, but this could depend on a million things. If you said "We, however, must acknowledge..." it would sound as if a contrast was being drawn between "us" and other people, which might sometimes be the intended meaning, but usually not.

Options B and C are impossible. Option A is equally acceptable to the original sentence. So I suppose the answer is D.

@BenKovitz My interpretation was different. As I said in my answer, there are languages is in which you are required to say things like "She said she will see me yesterday" - the tense is determined relative to the time of the utterance, not relative to the time that the speech is reported. My impression is that the OP may speak a language of that kind. I don't think the question is about the historical present, because otherwise the OP would have written "decides that she doesn't like staying home all day" and "tells her father that...," which he didn't do.