The correct option is A True
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 noun phrase is a word or a group of words containing a noun, that
functions as the subject, object or object of a preposition in a
sentence. A phrase does not contain a subject or a verb, or both of them (as opposed to a clause).
While expanding a noun phrase to noun clause, a subject and a verb must be added.
The underlined clause is an expansion of the phrase 'how to speak...', where the infinitive 'to speak' in the phrase is replaced by the verb "could speak" and the subject "she" is introduced, thus retaining the meaning of the phrase.
Hence the statement is true and option A is correct, B is incorrect.