bind 9 can not balance load with mode order cyclic

I configured bind as dns server on centos 8 and create a zone file named test.com.zone,the contents as follow:

$TTL 1D
@   IN  SOA  test.com.   root.test.com. (
                        2020072603     ; serial
                        1D      ; refresh
                        1H      ; retry
                        1W      ; expire
                        3H )    ; minimum
@          IN NS      master.test.com.
@          IN NS      slave.test.com.
slave       IN A    100.100.5.21
master       IN A    100.100.5.22
www   IN A   101.101.5.21
www   IN A   101.101.5.22
www   IN A   101.101.5.23
www   IN A   101.101.5.24
www   IN A   101.101.5.25
www   IN A   101.101.10.245
www   IN A   101.101.10.246
www   IN A   101.101.10.247
www   IN A   101.101.10.248
www   IN A   101.101.10.249

the Subnet Mask of ip in resource records above is all 16 bits,when i ping www.test.com from client for 10 times,the ip it allocates is 101.101.5.21 for 6 times and 101.101.5.22~25,it can not allocate the ip of 101.101.10.x,is it any limit for the ip in resource records? and then I modified the resource records in zone file as follow:

www   IN A   101.101.5.21
www   IN A   101.101.5.22
www   IN A   101.101.5.23
www   IN A   101.101.5.24
www   IN A   101.101.5.25
www   IN A   101.101.5.26
www   IN A   101.101.5.27
www   IN A   101.101.5.28
www   IN A   101.101.5.29
www   IN A   101.101.5.30

and I also ping www.test.com from client for 10 times,when the clients' operarte system is centos 8,it can Poll all the ip(101.101.5.2130) correctly,but when the clients' operarte system is centos 7,the ip it allocates is 101.101.5.21 for 5 times and 101.101.5.2226,why does it happen?