Generate a topic word for the given sentence. A topic word is usually the name of a person, place, animal, concept or object the sentence is focusing on.
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Question: the sunflower ("helianthus annuus") is a living annual plant in the family asteraceae, with a large flower head ("capitulum").

Answer: sunflower


Question: allan holdsworth (6 august 1946 – 15 april 2017) was a british guitarist and composer.

Answer: allan holdsworth


Question: the future of the earth will depend on many things, including increases in the brightness of the sun, loss of heat energy from the earth's core and change of the planet's orbit by the other things in the solar system.

Answer:
future of the earth