Attached are some of the questions from GMATPrep that I got wrong. The options marked with the bold black dot in the attachment are mine and are the wrong answers. The options marked by a square blue frame are correct as these are the correct answers marked by the software. However the software does not explain why a particular choice is correct and others are wrong. I will be very grateful if some of you can help justify why the correct choice is actually correct!
If you post one by one, you get good response.