The only plants in the garden were tulips, but they were tall tulips.

Very interesting question. I love it.



They may be tall compared to other tulips but not compared to other plants. Problem is the reference frames.

(A) The only dogs in the show were poodles and they were all black poodles. So all the dogs in the show were black.
Black is not relative.

(B) All the buildings on the block were tall. The only buildings on the block were office buildings and residential towers. So all the office buildings on the block were tall buildings.
No change of reference frame.

(C) All the primates in the zoo were gorillas. The only gorillas in the zoo were small gorillas. Thus the only primates in the zoo were small primates.
Oh yeah we got our answer right here. So similar. The gorillas may be small compared to other gorillas, but they may not be small compare to other primates.

(D) The only fruit in the kitchen was pears but the pears were not ripe. Thus none of the fruit in the kitchen was ripe.
Again, no change of reference frame.

(E) All the grand pianos here are large. All the grand pianos here are heavy. Thus everything large is heavy.
No change of reference frame.

(C)