Which species is an example of an autotroph?
a. bumblebee
c. frog spawn
b. ladybird
d. hawthorne tree

An autotroph is an example of a producer, something that builds its own nutrients from molecules such as carbon dioxide and water. In this case, the correct answer is d. A hawthorne tree uses the process of photosynthesis to produce nutrients such as simple sugars which can then be used to build organic molecules inside the plant to fuel respiration and other biochemical processes.