Which one is better for SEO Guest Blogging vs Social Media ?

A few articles on SEO will tell you,

that there are two main ways of promoting your blog and getting readers –
 Guest Posting, or Social Media. However, each work out only for a
specific group of people. This article will discuss the pros and cons of
 each, and will conclude with which is better for you, the blogger. What
 are they?

Guest Posting – Posting an article on another blog, as a “guest”. Thus
called Guest Posting. A guest post usually gives you 1 – 2 dofollow
links at the end of the article.

Social Media – Using social networking sites such as Facebook, Twitter,
and Google Plus to promote your blog. Using social media may have
different results based on the person.
Pros and Cons of Guest Posting/Blogging
Pros

Have around 2 dofollow links – These links are placed at the end of
the article, and thus are sure guaranteed to be seen by the readers. 

Have author description – The description tells people about you,
and your work, that other types may not offer.

The links are valued more than others – You may think, that a link
in the comments will give you same credibility of the link in the
article, so guest posting would be useless. Actually, that is wrong, and
links in the article are valued more by Google. Moreover, links in the
comments are usually nofollow, which gives no actual SEO benefit. Then,
links in the comment have less chance of being clicked, whereas links in
the end have more chance of being clicked, thus having more authority.
 

Target Audience - posting guarantees that your links are shown to
the target audience. This means, that if you have an SEO blog, and write
 a post about SEO, the only visitors will be the people searching about
SEO, not something entirely different.

Cons

The most obvious disadvantage is that you have to write a big, long,
suitable article everytime, for the actual owner of the blog. This is
not necessary in other methods.

You have to contact the admin, which could take time, and thus
results aren’t instant.

Conclusion

The links in the author description are high valued by Google and
Readers alike. On a blog with good ranks, this could be a potential
boost to your SEO. The only problem is that you have to write an article
everytime, which may not be everyone’s cup of tea.
Pros and Cons of using Social Media

Pros

 Very easy to do - All you have to do is copy the link from the

article, and paste it on your profile. No need of doing something tough.

Mass exposure - If you have 200 friends, you got your link to 200
people, with no actual work.

Easy to spread the word - Your post has chances of going viral, and
thus getting loads and loads of readers with this method.

Cons

The post is not shown to target audience. If you have 200 friends,
it’s not necessary that all 200 of them are interested in the topic.
Most probably, 5 – 10% of them would be interested.
Amount of clicks. Even if you have 20 – 30 people familiar with the
topic, there will be only a few that click the link. Maybe because the
info presented in that article is known to them, or they just miss the
link.

Conclusion

Upon reading this article, it would be obvious that only a certain type
of people get benefits from the methods.
Guest Posting is always appreciated, and if you are a good writer, then
you can establish trust. It is a bit difficult, I agree, but it gives
you an SEO boost if not readers.

Using Social Media is very easy, you can get views, but they are not
guaranteed. Thus, we can say that Guest Posting is great for people of
all types, but they do need to have a bit of writing flair. Social media
 may not prove beneficial to those who do not have friends interested in
 the topic, but if they have a page, with good number of likes, and they
 post the link there, it is sure to attract some attention, and get
readers