Explanation:

- Option 1: Transportation cost

- Moving from one place to another often incurs transportation expenses. This can include moving personal belongings or traveling with family.

- Option 2: Higher living cost in different place

- Settling in a new location can lead to increased living costs. This can be due to higher rent, food prices, or daily expenses in the new area.

- Option 3: Both a and b

- Migration typically involves both transportation and potential increased living costs. Both factors can significantly impact the financial aspect of moving.

- Option 4: None of these

- This option implies no costs are involved in migration, which is generally inaccurate.

Option 3: Both a and b is correct. "."