Final answer:
The nephew's interest in the property conveyed by Baker after her grandson's death is known as an Estate in remainder.
Step-by-step explanation:
In the scenario where Baker has conveyed a life estate to her grandson and stipulated that upon the grandson's death, the title will pass to her nephew, the nephew's interest is called an Estate in remainder. This term is used in property law to denote the future interest in real estate that will become possessory when a particular event occurs, such as the death of the life estate holder. The nephew's interest does not revert back to the grantor (Baker), which would be called an Estate in reversion, nor is it a temporary interest specified by a fixed period as in an Estate for years or a Periodic estate. In conclusion, the correct answer to what the nephew's interest is called is C. Estate in remainder.