What property in CSS is used for controlling the spacing between letters?

The property used for controlling the spacing between letters in CSS is known as letter-spacing. When you apply letter-spacing to an element, it adjusts the space between individual characters in the text, which can enhance readability or contribute to a specific design aesthetic. By using this property, you can specify positive values to increase the spacing or negative values to decrease it, effectively influencing how closely the letters sit next to one another.

The other properties mentioned, such as word-spacing and line-height, serve different purposes. Word-spacing adjusts the space between words, while line-height controls the vertical space between lines of text. Text-spacing is not a standard CSS property, which clarifies why it is not the correct answer. Understanding the unique functions of each CSS property enhances your ability to manipulate text presentation effectively.