B) to assure himself of its truth
The options given have you take a closer look at the words it's and himself. Option C changes "himself" to "hisself". "Hisself" is never correct. This means we have to decide if the correct answer is "its" or "it's". "Its", without an apostrophe, is the possessive form showing ownership. "It's", with an apostrophe, is a contraction meaning "it is". Let's plug them into the sentence "of it is truth" does not make any sense. Can "it" own truth? Yes, so "its" is the correct answer.
A : the house was a carnival
