The correct answer is B. Use a simple, easy-to-read font and decorate the border with formulas, images of planets, and books.
Step-by-step explanation:
A flyer is a common visual element more commonly used to advertise an event or product. Due to this, flyers need to be attractive while concisely providing information. In this way, it is recommended to use images and other visuals elements, and use simple fonts, for example, the use of cursive and similar should be avoided. Also, colors should be limited because complex fonts or the use of many colors do not allow the reader to understand the information easily. According to this, in this case, the most appropriate for Dan is to "Use a simple, easy-to-read font and decorate the border with formulas, images of planets, and books" because this idea includes visual elements such as images and also a simple font.