Identify each italicized subordinate clause as a noun clause, an adjective clause, or an adverb clause,
what the speaker said was not clear
o noun clause
adjective clause
adverb clause

The subordinate clause in the sentence is a noun clause.

Explanation:

A clause must have a subject and a verb. A noun clause is a subordinate (dependent) clause that functions as a noun in a sentence. Therefore, just like a noun, it can be: subject, object of a verb or of a preposition, or a predicate nominative. Noun clauses begin with words such as what, whatever, when, which, how etc.

In the sentence "What the speaker said was not clear" we can safely say we have a noun clause in "what the speaker said". It is a clause because it has a subject (speaker) and a verb (said). It is a noun clause because it starts with "what" and it functions as the subject of "was not clear". "Was" is a linking verb and "not clear" is the subject complement - and it is not a clause.

i cannot see any of the options

sentence lenght varies according to word choice.you select which word to use and that will require to use other expressions that collocate with the word chosen.sentence length will vary   according to the choice of words you make to express your ideas.