Which of the following statements best describes the domain of the functions cosine and arcos?
ACosine domain is all real numbers; Arccos domain is all real numbers.
BCosine domain is restricted; Arccos domain is all real numbers.
CCosine domain is all real numbers; Arccos domain is restricted.
DCosine domain is restricted; Arccos domain is restricted.
ACosine domain is all real numbers; Arccos domain is all real numbers.
BCosine domain is restricted; Arccos domain is all real numbers.
CCosine domain is all real numbers; Arccos domain is restricted.
DCosine domain is restricted; Arccos domain is restricted.