Btec business level 3 resit

I really need advice , I got accepted to the university that I want to go to with a conditional offer of DMM . I am predicted grades are DMM but I want to get DDM or DDD . I was thinking about what exam to resit should I resit unit 2 I got a near pass or resit both unit 6 and 7, I did the exams I think I am going to get pass on both. When I did the unit 6 mock I was 2 marks away from a merit. I got a pass in unit 3 exam and I was 6 marks away from getting a merit. I got distinctions in all my course work units so far and my aim is to get all distinctions on my coursework.

BTEC overall grades are determined based upon the points you get for each unit (summed-up). For exam-based units, the points you get depends not just on the grade, but also the mark - on a sliding scale. So the difference in points between just hitting the Merit grade boundary, and being one mark below it, isn't significant - it's just one point. When you consider that you need 176 points for a DMM and 196 points for a DDM, a single point won't make much difference. So don't chance a grade just for the sake of it. You could gain more points my improving you mark from just scraping a pass, to be just below a merit - both are a pass, but you get more points anyway.
What BTEC subject are you doing? (Business, Applied Science, IT, etc.) This will help us make sense of the unit numbers you've mentioned. This is important because some units are larger than other, so the same grade can be worth more points.
Finally, in which unit(s) do you think you can best improve the marks you obtained?

I am studying btec business

Thanks. A Pearson BTEC Level 3 National Extended Diploma in Business has four external (exam-based) units:
• Unit 2 - Developing a Marketing Campaign
• Unit 3 - Personal and Business Finance
• Unit 6 - Principles of Management
• Unit 7 - Business Decision Making
Unit 2 is smaller than the other three, so improving your result there will have less of an impact that with the other three.
You say above that "unit 2 I got a near pass". A near pass in that unit earns you between 6 and 8 points (depending on whether you're at the bottom, middle, or top of that grade band. If you resat this and managed to get a pass, it would earn you between 9 and 14 points - again depending on where you mark was compared to the grade boundaries. So going from the mid-score for a near pass (7 points) to the mid-score for a pass (11 or 12 points) would gain you an extra 4 or 5 points.
You say you think you passed Unit 6 and Unit 7. A pass in these units earns you between 12 and 19 points each. So even staying within the "pass" grade, you could gain an extra 7 points by gaining more marks.
Unless you have some reason so suspect that you can significantly improve you Unit 2 score, I'd leave it - it's not worth enough points. Which of the remaining three you opt to retake depends entirely on where you think you can improve the number of marks you obtained originally.

Thank you. I think i am not going to retake it.