Step 1: Understand the idea:
Fashion and textile trends change often. A designer has to keep up with new colours, motifs and styles.
To do so, the designer needs sources of information.
Step 2: Find the best fit:
Reference material means books, magazines, journals, trend reports, museum collections, photographs and websites.
These give a designer fresh ideas and show what is new in the market.
So a designer must be aware of various reference material.
Step 3: Why the other options are weaker:
A newspaper is only one source and does not cover design trends in depth.
Colour charts help only with colour choice, not with all design changes.
A repeat pattern is the design itself, not a source of information.
Final Answer:
The blank is filled with Reference material, option (B).