Application without family members'presence

Hi, I'm Malaysian. I've been invited to attend a conference in Sun Yat Sen Business School, Guangzhou as one of the paper presenters. I'm also planning to bring my wife and three kids together. ? Do they have to come to the Embassy for application? In other words, can I do that on behalf of them with complete documents? What are the supporting documents for the application? In travel information should I tick for " business" ?. Thank you