(There's no video for THINK C 4.0 yet. Please contribute to MR and add a video now!)
Symantec THINK C version 4.0 from 1989.
Comes on four 800KB floppy disk images.
Think_C_4.0.sit (1.11 MiB / 1.17 MB)
THINK C v4.0 floppy disk images / compressed w/ Stuffit
Mac OS 4.x - Mac OS 7.x
Emulating this? It should run fine under: Mini vMac