Which option best describes an example of when to use combination CSS selectors?

a$.)$

When all the subheadings need to be orange instead of the default black font color

b$.)$

When the first letter of a paragraph needs to be red instead of the default black font color

c$.)$

When all the paragraphs need to have a black background with white font color

d$.)$

When the main heading on every page needs to be underlined