Answer: Ok, so you want to negate the whole statement, first you if you want to negate the all dogs have fleas you need to find at least one dog that doesn't have fleas.
all the answers follow the same way of thinking.
a) All dogs have fleas. ---- At least one dog doesn't have fleas.
b) There is a horse that can add. ---- all horses can't add.
c) Every koala can climb. ----- at least one coala cant climb
d) No monkey can speak French.---- at least one monkey can speak french
e) There exists a pig that can swim and catch fish. --- all pigs can't swim and catch a fish