CJK charset does not display correctly in individual "Download responses " function

[aec2016]

For the latest stable relase of Moodle v3.5.3, the chinese characters in the response part displays wrong as "?€????" in the CSV file exported by the individual "Download responses" function. Please check the following screenshots:

The CVS exported as belows:

As you can see in the red circle, the chinese character is displayed wrongly as "?€????".