Those devices all have different default I2C addresses so you can connect them to the same bus (SDA and SCL) with no problem. You use only one pair of pullup resistors, typically 2K2 to 4K7. Pay attention to the address selection pins on each of the modules.
There are these comments complaining that some of the literature on the MPR121 that gives the wrong I2C device address: https://community.freescale.com/thread/62485
When in doubt, connect one device at a time to the I2C pins and run the I2C address scanner: Arduino Playground - I2cScanner Then, connect them all to the same bus and rerun the scanner. It should see all of the devices respond.