8 .6 3 5 7

Unit decimal point 10 percentile1000th percentile

5 is on one thousandth, so it can't be a, and "one thousandth" is a counting unit, not a multiple. Unlike "five apples", it can have several. Just in which position, there are several. It's like thinking of a thousandth as a cake, cutting a thousand dollars with a * * *. Take five of them, which is one thousandth of five. So we also ruled out c, leaving only B.

Do you have any credits? If you learn it, you will understand it better. You can't do it unless you ask your parents and teachers. You'll find out later. I remember we learned it in the fifth grade.