what is the largest living organism on earth

The largest living organism on Earth is a fungus called Armillaria ostoyae, also known as the honey fungus.

Explanation:

• This fungus exists in the Malheur National Forest in Oregon, USA.
• It covers an area of about 2,385 acres (965 hectares), which is roughly 4 square miles.
• The organism is connected by an underground network of mycelium (the vegetative part of the fungus), making it a single, continuous organism.
• It’s estimated to be thousands of years old.