Answer:
c, A ruler who has full control over a country
Explanation:
A).
<span>the consistency and clarity of the message</span>
A subordinate clause is a clause that contains both a subject and a verb, but cannot stand on its own because it does not convey a complete message. It needs the main sentence in order to clearly understand its thought. The subordinate in the given sentence is: the children enjoyed. This is an adjective clause, which modifies the noun "book". It is not introduced by any subordinating conjunctions.
In this sentence, the word "throughout" is used as a preposition.