In this task, you are given a string with duplicate characters ocurring in the string. You need to return the character which is ocurring with the maximum frequency. In case of a tie, return the character with the least ascii value.

Q: hlkdrvgmoezdqqhrlqknzxspystcayvexjwbifct

A: q
****
Q: ujksgfumsawrdverpmngnjecntcxxxznwcoxxhkx

A: x
****
Q: nusnjxdgvvlgusjbajvjcttxmzafkbaxwxlxzvrr

A:
x
****