The first picture, only one row, the first row is two smiling faces.

In the second diagram, * * * has 2 lines, the first line has 2, and the second line has 2+2=2*2=4.

In the third diagram, * * * has three rows, the first row has two rows, the second row is 2+2=2*2=4, and the third row is 2+2+2=2*3=6.

Obviously, the nth graph * * * has n rows, the first row has 2, the second row has 4, the third row has 6, ..., and the nth row is 2n.

So the 30th digit, * * * has 30 rows, 2 in the first row, 4 in the second row, 6 in the third row, ... 60 in the 30th row.

This is an arithmetic series.

S=(2+60)*30/2=62*30/2=930 (piece)

Therefore, the 30th number * * * has 930 smiling faces.

So, choose B.

I hope you can adopt it.