California Code, Probate Code - PROB § 9980

(a) Where an option to purchase real or personal property is given in a will, the person given the option has the right to exercise the option at any time within the time limits provided by the will. For the purposes of this section, if a time limitation in the will is measured from the death of the testator, that time shall be extended by the period between the testator's death and the issuance of letters testamentary or of administration with the will annexed or by six months, whichever is the shorter period.

(b) If the will does not provide a time limit for exercise of the option, the time limit is one year from the death of the decedent.

(c) Subject to subdivision (b), if the option given in the will is exercisable under the terms of the will after the time that the estate would otherwise be closed, the property subject to the option shall be distributed subject to the option.