Only Jehovah’s Witnesses
I think this says it clearly enough: "Only Jehovah's Witnesses, those of the anointed remnant and the "great crowd," as a united organization under the protection of the Supreme Organizer, have any Scriptural hope of surviving the impending end of this doomed system dominated by Satan the Devil." Watchtower 1989 Sep 1 p.19
But here
What do people need to do to be symbolically marked for survival? (Ezekiel 9:4) They need to react favorably to the preaching work that is taking place, put on the Christian personality, dedicate themselves to Jehovah, and loyally support Christ’s brothers. Those who do these things will receive the mark of survival during the coming great tribulation.--Watchtower 2016 Questions from Readers p.17
What is the mark? It is the evidence, as if displayed on their uncovered foreheads, that such sheep are dedicated, baptized disciples of Jesus Christ and that they have put on the Christlike new personality. These sheeplike ones become one flock with anointed Christians and assist them in their vital work of marking still others.—Watchtower 2008 7/15 p.5
In ancient times slaves were often marked on the forehead to be clearly identified. Distinctive marks on the forehead and elsewhere might also show that a person worshiped a certain deity. So, in our day, what is the distinctive, lifesaving mark that clearly identifies its bearers as true worshipers and slaves of Jehovah?-Watchtower 1987 4/15 p.11
The mark” is the evidence that they are dedicated to Jehovah, baptized as disciples of Jesus, and involved in cultivating a Christlike personality.-Worship the Only True God book Chap. 13 p.120