Explanation:
relative clause
it modifies noun phrase by some grammatical tools
example
my friend who is coming from America is coming to the dinner
here who is used to indicate the noun phrase
subject verb agreement
A subject and a verb must agree, even when other words or phrases come between them.
example
The flock of geese is flying south for the winter.
The subject is flock, so the verb should be is flying.
The figurative language is personification
C. uses
Uses is the only word that words in this context. The advertisement isn't keeping anything. It hopefully creates a desire in the consumer to buy a product but it doesn't create a technique. It also does intend to convince buyers but it can't intend a technique either. Techniques are used so this is the most accurate and precise replacement for has.
