A new political scorecard, from the group that has already dogged White House hopefuls on the campaign trail with more than 70 direct questions related to environmental issues, shows that Bernie Sanders is the only presidential candidate with a spotless record when it comes to the climate movement’s top priorities.

On issues ranging from Arctic drilling to fossil fuel divestment to fracking to #ExxonKnew, the senator from Vermont has taken strong stances—going as far as to call for an outright ban on fracking just a few weeks ago, according to 350 Action, the 501(c)(4) political arm of 350.org.

While his rivals for the Democratic nomination, former Secretary of State Hillary Clinton and former Maryland Gov. Martin O’Malley, share many of the same positions, Sanders is the only candidate that checks every box.

Indeed, as Rebecca Leber wrote at The New Republic on Wednesday, “there’s one environmental issue where Sanders truly stands apart: He wants to ban hydraulic fracturing outright. Clinton and O’Malley have proposed lesser measures, and show no sign of going further.”