Select the correct answer.
 In terms of design principles of an advertisement, to what does balance refer?
 OA the controlling of the advertisement's color scheme
 OB.
 the brightness of the advertisement
 OC
 a proper sequence of the advertisement's content
 OD. the control of size, tone, weight, and position of the elements used in the advertisement
 OE.
 to ensure that all elements of the advertisement blend with each other and are compatible