Ruth wants to purchase a new gaming laptop. She wants to compare two of the latest models of gaming laptops$-$with similar build, quality, and hardware specifications $-$ from different manufacturers. Ruth reads reviews of each product on reputable online forums before making her decision. In this scenario, Ruth seeks data

c$.$

from a non$-$marketing$-$controlled information source

b$.$

through her own knowledge

a$.$

from a marketing$-$controlled information source

d$.$

through an internal information scarch