Automatically tweets posts published on a blog using rss technology. select one:
a. tweetdeck
b. twitpic
c. twitterfeed
d. twitterholic

Letter c is correct. twitterfeed.

Explanation:

 Twitterfeed is a tool that uses rss technology to automatically post to various social media, such as blogs, with the main purpose of keeping the social network updated without any effort, since the posts occur in a scheduled and constant way.

This tool is widely used by people and companies that work with social media. Online presence and updating is important to generate content and maintain the interest and engagement of the public.

Vendor B

Explanation:

Using letters to represent each vendor and the symbol < to express wich is less expensive the information in the problem can be resumed like this: A<C, B<C, B<D, D<A.

These expressions involving two vendors have at the left the less expensive vendor and at the right, the more expensive, every vendor that appears at the right in one of the relations can't be the less expensive, this disqualifies C, D, and A, then less expensive vendor is B.