Which materials are considered secondary data?
photos and letters given to you by another person
books and articles written by other authors about their studies
information that you have gathered and now have included in your results
responses from participants whom you both surveyed and interviewed

The correct answer choice from the options given, to answer the question: Which materials are considered secondary data? would be: Books and articles written by other authors about their studies.

Explanation:

The reason for this being the correct choice comes from learning that secondary data research is commonly described as using data and information provided by other authors, experts and researchers on a given topic, and that would answer the original research question. In this way, a researcher may gather already existing information on his topic of interest, learn about the background information and the knowledge already established, and work from there, instead of re-inventing something that was already there.

new communications technology has affected the way social movements are organized because nowadays, social movements rely on social networks and the media to get different people with a similar way of thinking in contact, and thus, get them to mobilize for a greater cause.

individuals only participate in collective action when they feel identified with it. is in this aspect that social media becomes relevant, because it guarantees communication among all individuals and organizes the social actions that are going to be carried out, i.e., the social movements.

in addition, being covered by the media is important to validate the message and make it relevant in the social agenda, as well as to reach more people who can share interests, appealing to public sympathy for their cause.

in conclusion, it is by social networks and social media that social movement is given birth; by connecting different individuals with similar ideas and organizing them to mobilize for a greater cause.

answer; strength of association;