A combination of both will be preferred because on the one hand your website should have quality contents for people to find and study, and on the other hand it should have some good links pointing to its pages to convince search engines that it serves better ranks and stronger traffic shares. Make your web pages for people, keep them updated with original contents and in the meanwhile do not forget to build links, especially the ones originating from relevant sources and portals.
Content and links are important to SEO. You cannot really choose one because both of them are needed for the betterment of your website. Like in a plane, you cannot just ignore the right wing to focus on the left wing. Both of them are needed in order to have a good flight.
Content is King and link is Queen for website that statement shows that both are an Important part of Website when you need to optimize your website for higher search ranking so always putting fresh and quality content in website and making relevant link.