Final answer:
To apply the same declarations to two types of elements regardless of their relationship, use the universal selector in CSS.
Step-by-step explanation:
If you want to apply the same declarations to two types of elements, independent of their relationship to each other, use the universal selector in CSS. The universal selector, denoted by an asterisk (*), targets all elements on the webpage. By applying styles to the universal selector, those styles will be applied to all elements.