You need to test your CTA, depending on and relevant to your content. Let’s say if your content is more about education and you are referring to other articles or case studies, links as CTA might be more suitable, while when promoting other programs, or services or if you want the visitor to buy something, then buttons or banners could be more appropriate.

Use CTA you think it suits better for your marketing efforts.

Further important point is that CTA has to be clear and needs to follow the content. You may announce at the beginning of the article about some “discover” or “very important info” you will reveal at the end of the article and entice reader to read through the whole article.

Such CTA “read through the article” can improve the readiness of the reader to read through your article, and thus, to stay longer on your blog post, or any other created content, what in return can result with more “Google trust” and finally bring you better rank in the SERPs. As you can see, CTA can also increase your page rank.