Explanation:

- Town A:

- Difference between males and females: 15,000

- Ratio: 7 : 13

- Let males be 7x and females be 13x.

- 13x - 7x = 15,000 -> x = 2,500.

- Males in A = 17,500.

- Town B:

- Difference between males and females: 20,000

- Ratio: 6 : 1

- Let males be 6y and females be y.

- 6y - y = 20,000 -> y = 4,000.

- Females in B: 4,000

- Ratio between females in B and males in E: 8 : 17

- Males in E (z) = (4,000/8) * 17 = 8,500.

- Ratio between males in E and males in A:

- Males in E = 8,500; Males in A = 17,500

- Ratio = 8,500 : 17,500 = 17 : 35

- Answer:

- Option 2: 17 : 35