Final answer:
Middle children feel the need to surpass the achievements of older siblings, aligning with Adler's theory of how birth order can influence personality.
Step-by-step explanation:
Alfred Adler's theory of birth order suggests that different positions within family birth order can shape an individual's personality. Among the options given, C) Middle children often feel the need to surpass the achievements of older siblings is the one that aligns with Adler's theory. Adler proposed that firstborns often become overachievers to compensate for sharing parental attention with subsequent children. Middle children might feel less significant and therefore can be motivated to surpass their older siblings as a way to gain individuality and recognition. The youngest children may end up being more spoiled and, therefore, may not align with the idea of being perfectionists as stated in option A. Only children, according to Adler, might be more likely to exhibit characteristics akin to firstborns due to having no siblings with which to compete for parental attention, contradicting option D.