Liam and Isla Are Husband and Wife and Have Always

Liam and Isla are husband and wife and have always lived in a community property state. At the time of Isla's prior death, part of their community property includes: Under Isla's will, all of her property passes to Liam. After Isla's death, Liam's income tax basis in this property is:

A) $2,500,000.
B) $3,500,000.
C) $7,000,000.
D) $8,000,000.
E) None of the above.