which Purpose of visit to choose when visiting short-term for busniess reasons

Hello there,

I have a few questions regarding the application form .

My purspose of travel is that I will visit some fairs in China ( Hong-kong, Shanghai and Beijing) to present the company.

2.1 Major Purspose of you visit = Which option should I choose if travelling as per above
1.22Marital status = if engaged, should that be chosen or do I choose "single"
The photo = what is the measurementand requimnets other then already written in the application?

Thank you for your support!