A.
The animation-timing-function specifies the speed curve of animation, its default value is linear, which means that the speed of animation is the same from beginning to end.
B.
The animation-duration specifies the seconds or milliseconds it takes for animation to complete a cycle, its default value is 0.
C.
The animation-iteration-count specifies the number of times the animation is played, its default value is infinite, which means playing animation infinitely.
D.
The animation-delay defaults to 0, which means animation is paused.