Existing claims related to product warranties and litigation as of December 31, 2010, indicate that it is probable that a liability has been incurred. However, as of December 31, 2010, the amount of the obligation cannot be reasonably estimated. Based on these facts, an estimated loss contingency should be
a. disclosed but not accrued
b. classified as an appropriation of retained earnings
c. accrued
d. neither accrued nor disclosed