UK Standard visitor visa type for Tourism or Family?

I am planning to travel with my wife from India to meet her sister in the UK. Her sister is a British citizen and lives in Scotland. We are planning to visit London for few days and then visit the sister's home in Scotland. We are Indian citizens and we will be doing some tourism as well.

After selecting standard visa, I have to choose the reason for the visit, e.g., Tourism, Family etc. Which should I select, since we will do both?

As far as I understand, based on the selection, the application type will be different and I dont want to make a mistake.