Answer:
(a) and (d) are correct
Explanation:
AIDS is a disease that's usually transmitted by sexual contact and breast feeding.
Sample Response:
Bacteria are helpful because they produce oxygen, which our bodies need to breathe, and they help us to digest the food we eat. Bacteria are also helpful because they are used in medicine to help us overcome disease. Bacteria are harmful because they can cause tooth decay and illnesses that can be either common or quite serious.
This is a sample response, so it's 100% correct. Peace!
It is definitely false. Remember that regarding adult brains, the older the brain gets the more connections you use to lose. So this statement is false. Hope this can help you a lot