This is an average-difficulty question. Statement 4 says 'it is an example of an ancient belief system...'. You must ask what noun the pronoun 'it' is referring to. It can only refer to the noun phrase 'the notion of balance'. Thus 3 and 4 form a pair. Now we can have 3412 or 3421 2 has the phrase 'these parts', what noun is 'these parts' referring to. It is referring to the noun 'component parts' in statement 4. Thus, 342 form a pair. In fact, 4 and 2 form one unit. 'Such a belief' in 4 refers to the belief in 4 . Thus we must have 3421 in sequence.