Original sentence: A response to Lindzen's piece attempts to discredit the basis for his claims as allegedly not being supported by currently available data..  The environmental advocacy group Environmental Defense claims that organizations that Lindzen is a part of, or has received funds from ExxonMobil..
Edited sentence: David Lawrence in a response to Lindzen, challenged the factual basis of Lindzen's arguments..  The environmental advocacy group Environmental Defense claims that organizations that Lindzen is a part of, or has received funds from ExxonMobil..