My thought process for this one: In DNA mismatch repair for bacteria there is a parent strand and a newly synthesized strand. The parent strand is methylated prior to replication to allow it to be differentiated from the new strand in the case of mismatching. The new strand is identified by the lack of methylation and then degraded by endonucleases. So I used this logic to think altered methylase (decreased activity) allows for more DNA to be degraded by endonucleases. Not sure if its the best logic but it got me there lol