Correct Option: D

We can add prefixes automatically during the time of development. This can be done using tools like PostCSS and Autoprefixer. Autoprefixer has an online version that allows to enter non-prefixed CSS on left, and gives prefix-added version on the right. Gulp is an open source kit for js i.e. JavaScript. A javascript utility that emulates CSS3 pseudoclasses and attribute selectors are called selectivizr. Moo Tool is a javascript framework which is object oriented.