In building the Parthenon, how did the architects use engineering to counter the various negative optical effects?

columns tilt slightly inward

and Doric columns swell slightly near the center  

Explanation:

solution

we know that  Parthenon is the finest example of Greek architecture

and Parthenon is design on marvel and featuring massive column that contrasting

so architects use engineering to counter some negative optical effect are as

columns tilt slightly inward

and Doric columns swell slightly near the center  

i believe it is a. a segment : )