The correct answer is:
A. They are all eukaryotic organisms that have nuclei in their cells.
Frogs, worms, and pine trees are all eukaryotic organisms, meaning their cells contain a nucleus and other membrane-bound organelles. Option C is incorrect because pine trees are autotrophic (they make their own food via photosynthesis), while frogs and worms are heterotrophic (they consume other organisms for energy). Option B is incorrect as frogs, worms, and pine trees are not prokaryotic. Option D is also incorrect because, while frogs and worms are heterotrophic, pine trees are not; they are autotrophic.