Are OneDrive, Google Drive cloud storage services safe against cyber attacks (e.g. ransomwares/malwares) ?

[M A Hossain Pintu]

Last month my pc got affected by a ransomware attack and all of my files in different drives were encrypted. However, files in C (windows) drive were not encrypted i.e. they remained as before. I posted here and knew about this problem through various replies. Now, I wish to make backup of my files/docs/photos into Onedrive and Google drive cloud storage. So, my question is are these services safe against such cyber attacks and how my C drive was protected but others not ?

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