Which astronomical advancement was attributed to the mayans
a.

they calculated the exact solar year as 365.25 days.

b.

they observed the moons of jupiter.

c.

they were aware that earth orbits the sun.

d.

they calculated the various phases of the moon. ?

Maya astronomer-priests looked to the heavens for guidance. They used observatories, shadow-casting devices, and observations of the horizon to trace the complex motions of the sun, the stars and planets in order to observe, calculate and record this information in their chronicles, or "codices".

Explanation:

if the type of the food available changes, then the frequency of beak types will change, because birds with beaks more suited to the available food will be more successful over time.