In a memo field, all the displayed text must use the same format

We wish to modify a class while keeping it backward compatible. Which of the following can we successfully do?

A. Remove a function. B. Change a function’s return type from a float to a char C. Add another parameter to a function D. Add a new function to the class

Explain the styles to change each of the following in HTML: kerning, tracking, leading, and indentation of the first line.

What will be an ideal response?