I would say A. Because c and d r very dangerous if u think about it. And b is right in some situations. But if u do a then people can see whts going on if something happened because of the light. and it is safe. If wrong let me know. :D
A, I hope this helps you out
mammogram, allows the doctor to find exact location of lumps and determine what they look like
Answer:
B. Changing passwords frequently makes you likely to forget which isn't helpful, using a personal e-mail address is unprofessional, only limiting the number of people and keeping it down to just enough people who need to see it can see it is truly helpful.