'S' will be the first part of the given sequence as 'not merely' is making a link with 'Man is'. 'P' will follow next as it indicates that man is not merely a biological being. 'R' will come next because the phrasal verb 'confined to' is used in connection to 'being a biological being' in P. 'Q' will be the last part as confinement is talked in respect to 'physical and material needs'. Hence, SPRQ is the correct sequence. Thus, option (d) is correct.