10/(40+ 10+30+20)= 1/ 10

30/(40+ 10+30+20)=3/ 10

20/(40+ 10+30+20)= 1/5

Therefore, the number of people drawn from four tour groups during stratified sampling is:

Group A: 20 2/5 = 8 people.

Group B: 20110 = 2 people.

Group C: 20.3/ 10 = 6 people.

Group D: 20. 1/5 = 4 people.

And because each place requires one person to visit, everyone only visits one city, and the people in Group B don't visit Chengdu.

So it is divided into the following steps, and then it is solved step by step: (The numbers arranged and combined are always big at the bottom and small at the top)

Group b 1 person was selected: c 21c 31a 43 =144 species.

Group B: A32C42A22=72 kinds.

If there are no selected people in Group B: A44=24 kinds.

So, in a word, there are 240 different options. The answer is B.

. . . . . . . . . . . . . . . . . . . . . . . . I hope the landlord will adopt it! ! ! Finally, I wish the landlord study and progress!