The answer is C! I read this book.
The answer C correctly uses possessive form and is the right answer. It's not A because there is only one George so the apostrophe is in the wrong place. In B, there's not even an apostrophe and it's not clear as to whether there is only one cousin or two or more cousins. In answer D, here should not be an apostrophe for develops.
Answer : Option C) Actually
Explanation : "<em>An adverb is a word or phrase which modifies the meaning of an adjective, verb, or other adverb, expressing manner, place, time, or degree for e.g. gently, here, now, very". </em>There are some adverbs, which are like sentence adverbs,that can be also used to modify the whole sentences.
Here amongst the given options; "Actually" is the word that satisfies the condition of being an adverb as it is modifying the other adverb "really."
Rest all options are a form of adjective.