Anterior or Posterior

My apologies in advance to any who find this query offensive.
I was in an observational state of mind during lunch today. When what could be described as, an attractive lady walked by. I noticed that all eyes in the vicinity were instinctively drawn to certain features of her anatomy. My question is, what are the basic scientific reasons/theories as to why we men are attracted to the anterior and/or posterior of the female, psysique?

The Darwinian, never-ending drive to reproduce. Or did the question go over my head?

It is a primal and innate desire of man to be attracted to a mate that is healthy so that the offspring is healthy and his genes can have better chance of survival in the gene pool.

Figures with proper curves are a sign of good health and fertility.

It’s not just that. It’s also predominately social. As we grow up, we internalize the behavior of reacting a specific way to a specific body time. It’s Pavlovian on a global scale - it’s socially unacceptable for a man to not find attractive a woman who fits a certain range of body types. So we learn to avoid the unspoken stigma by doing whatever it is we do to express, shall we say, “aesthetic appreciation.”

Of course, evolution is the reason that the social norms direct men to appreciate the body types that they do instead of something else.