undeniable

After all, it is undeniable that the B.R. standard coach scored highly in comparative trials with other European railway vehicles on the Continent a few years ago, so that B.R. civil engineers must share responsibility for any defects in its behaviour over here.

1960 December, “Talking of Trains: The riding of B.R. coaches”, in Trains Illustrated, pages 705–706

If successful, Edison and Ford—in 1914—would move society away from the[…]hazards of gasoline cars: air and water pollution, noise and noxiousness, constant coughing and the undeniable rise in cancers caused by smoke exhaust particulates.

2006, Edwin Black, chapter 1, in Internal Combustion

The connection between dictionaries and standardised forms of language is undeniable, yet, at the same time, not well understood.

2012, James Lambert, “Beyond Hobson-Jobson: A new lexicography for Indian English”, in World Englishes, page 18

The dispatches […] also exposed the blatant discrepancy between the west's professed values and actual foreign policies. Having lectured the Arab world about democracy for years, its collusion in suppressing freedom was undeniable as protesters were met by weaponry and tear gas made in the west, employed by a military trained by westerners.

2013 June 7, Gary Younge, “Hypocrisy lies at heart of Manning prosecution”, in The Guardian Weekly, volume 188, number 26, archived from the original on 14 Mar 2016, page 18