default or selected kernelversion does not have config value CONFIG_EXT3_FS_XATTR.
Result is shown for kernelversion 6.5.1

Ext3 extended attributes

configname: CONFIG_EXT3_FS_XATTR

Linux Kernel Configuration
└─>File systems
└─>Ext3 extended attributes
In linux kernel since version 2.6.20 (release Date: 2007-02-04)  
Extended attributes are name:value pairs associated with inodes by
the kernel or by users (see the attr(5) manual page, or visit
<> for details).

If unsure, say N.

You need this for POSIX ACL support on ext3.