<prompt> Urea cycle is linked to TCA cycle by -ArginineOrnithineOxaloacetateFumarate  <response>: Ans. is d i.e., Fumarate Ref: Harper 29the p. 276-277o Fumarate is released during urea cycle, which is an intermediate of Krebs cycle, thus linking the two.Both urea cycle and TCA cycle have been explained in previous years. 