Answer:
C. ATA Secure Erase
D. Smash the USB drive
Explanation:
Zero fill utility is a specialized way of formatting a storage device particularly secondary storage such as hard disk, flash drive e.t.c. In this process, the disk contents are overwritten with zeros. Once this has been done, undoing is essentially hard but possible. In most cases, this might just mean that the data content is corrupt and as such might still be recovered, maybe not in its pure entirety.
Formatting the drive on another hand does not essentially mean cleaning the drive and wiping off data. It just means that operating systems cannot see those data contents anymore. They are still present in the drive and can be recovered.
ATA Secure Erase is actually a way of completely and permanently erasing the content in a drive. Once the function has been done, undoing is not possible. Both the data content and even the data management table will be completely gone.
Smashing the USB drive is the surest way of cleaning data as that will permanently destroy the working components of the drive such as the memory chip. And once that happens then there's no drive let alone its contents.