Answer:
: The study of the spending characteristics and purchasing power of the consumer who are within your business's geographic area of operation; a research method for defining the market parameters of a business.
The answer is (d.) choose only the visuals that are easily understood.
The main purpose of the visual aids is to help improve the understanding of the audience to the presentation. It clarifies and reinforce the key points of the topic. So it's important to choose the appropriate visual that could help the presentation easily understood.
Sound/ music colors and maybe just like drawing
the ability of creating fine works of art like drawing, painting, sculpting, composition of music,etc is called art skill
hope it helps