What is the grammatical function of the bolded noun clause in this sentence?

The most important person right now is whoever is willing to do the job.
Responses
A subjectsubject
B direct objectdirect object
C prepositional objectprepositional object
D predicate nominative

D predicate nominative

In the sentence "The most important person right now is whoever is willing to do the job," the bolded noun clause "whoever is willing to do the job" is functioning as a predicate nominative, also known as a subject complement. This means it follows a linking verb ("is") and renames or provides more information about the subject ("The most important person right now").