Ksenia is excited about going to her first sorority formal next month. However, she is concerned that she does not have anything appropriate to wear. Since realizing that she needs to get a new dress, Ksenia has started paying attention to advertisements, looking at fashion magazines, visiting retail stores, and browsing the Web for the latest fashions. Ksenia is engaged in:

a$.$ internal information search.

b$.$ problem or opportunity recognition.

c$.$ external information search.

d$.$ purchase decision