The correct option is B False
A noun clause is a dependent clause that functions as a noun. It usually
begins with what, whatever, whom, that and other such relative
pronouns. A noun clause can act as a subject, object, predicate
nominative or object of a preposition, in a sentence.
A verb complement is a word, a phrase or a clause that is added to the verb to complete its meaning.
The noun clause "what she just bought" is not an object, it's a verb complement; the verb "want" makes no sense if it isn't followed by a word that complements it. The noun clause here functions as a verb complement.
Hence the statement is false and option B is correct, A is incorrect.