Which of the following is not a black hat link building technique?

[makoo]

Which of the following is not a black hat link-building technique?

Buying links.
Creating quality content.
PBN links.
Link farms.

[jayam]

Black Hat SEO is most commonly defined as a disapproved practice that nevertheless could increase a page's ranking in a search engine result page (SERP). These practices are against the search engine's terms of service and can result in the site being banned from the search engine and affiliate sites.

[yuva12]

Black hat marketing is the use of unethical (and sometimes, but not always, illegal) strategies to promote online business. In contrast to ethical “white hat” strategies, black hat strategies use deception and manipulation to accomplish their objectives (See also Ethical Marketing).

[jayammrg]

Black hat link building tactics are techniques used to drive traffic to a website by exploiting website loopholes, enabling a site to rank higher than it should through "organic" search means. ... A link farm is a website that features a series links to other sites without any content with inherent value on that page.

[chandrao7]

Black hat SEO techniques, encapsulated by spamdexing, entail manipulating how search engines perceive the relevance of a Web page in a way that is often inconsistent with the search engines' guidelines. Hidden text, cloaking, and blog comment spam are examples of black hat SEO.

[dennis123]

Creating quality content is not a black hat link-building technique.

[vjvysakh]

Creating quality content.

[jesica]

The following SEO tactics are considered black hat and should not be exercised at all if you want to stay above board with Google and other search engines: Content Automation. Doorway Pages. Hidden Text or Links.