Option B
:hover the pseudo-class that should be used to perform this function.
A CSS pseudo-class is a keyword attached to a selector that designates a specific state of the chosen element(s). The :hover pseudo-class is applied to style an element when the user’s pointer is over it. It mustn’t be limited to links, although that is the usual fair use case.
a:hover must appear after a:link and a:visited in the CSS definition to be powerful. It should resemble third in order (subsequent the :visited pseudo-class). Pseudo-class names are not case-sensitive. The syntax is
a:hover {
color: blue;
}