In the Centerville Botanical Gardens, all tulip trees are older than

The right answer here is E. Inference questions can sometimes be tricky since you have to pick an answer that is true 100% rather than something that is just 'mostly true'. However, the best way to do this is to instead eliminate answers that have even the slightest potential to be false. This means that you're eliminating based on "can be false". When you have 'some/sometimes' statements, the best way to do this is to put a 'not' before the some/sometimes and see if its possible that it can be true.

We know: All tulips older than maples, All maples older than dogwoods, most Sycamores older than Maples but we don't know about the oldest Sycamores in relationship to tulips, or the youngest in relationship to dogwoods.

A - Dogwoods are all younger than any of the tulips, so this is definitely false. OUT

B - Anything is possible with the Sycamores, and some dogwoods could be as old as the youngest ones. But, it's also just as likely that they may not be, so this can be false. OUT

C - Again, anything is possibly with the sycamores. It could be that some of them are younger than the oldest dogwoods, but it could just as easily be not. OUT

D - Once again, it is possible that the all the tulips are older than the oldest Sycamores, so we must eliminate because it can be false. OUT

E - It's simply not possibly that no sycamores are younger than the youngest tulips, since we know that some of them are younger than maples, and ALL maples are younger than the youngest tulip. Hence, this answer MUST be true.

- Matoo