Mortal Kombat Arcade Edition v1.0a is the definitive version made by Linkuei.

With his permission, Rael G.C. made some graphical improvements:

• Improved Kano, Rayden, Liu Kang, Sub-Zero, Scorpion and Sonya at the character selection screen in order to get closer to the arcade.
• Improved Sub-Zero fatality to show the front size of the heads.
• Reduce the “greenness” of the Goro’s Lair new parallax.
• Fixed Johnny Cage skin colors.
• Improved mini avatar for Sub-Zero, Scorpion, Liu Kang, Johnny Cage, Kano.
• Reworked Rayden stance animation and victory standing, restoring the “blue” eyes.
• Reworked Scorpion/Sub-Zero head on victory standing.
• Reworked Sub-Zero sprites on stance animation and victory standing.
• Improved The Pit cloud colors to match the arcade.
• Fixed Sub-Zero walking animation (it was broken, with disappearing arms).
• Fixed Sonya belly, hair and shoes colors.
• Fixed Liu Kang stance animation and victory standing.
• Fixed Kano victory animation (first frame was 2 pixels misplaced to the bottom)
• Made the Genesis soundtrack order the default option.
• Fixed the checksum

There is a detailed description of the changes in the character selection screen here: https://www.romhacking.net/news/2660/

• Database match: Mortal Kombat (USA, Europe) (Rev A) (Beta)
• Database: No-Intro: Genesis (v. 20210226-213851)
• File/ROM SHA-1: 2C4A0618CC93EF7BE8329A82CA6D2D16F49B23E0
• File/ROM CRC32: 33F19AB6