Charlie prepares a tax return for Taxpayer X that includes a claim for the ETC. Charlie A. May rely solely on Taxpayer X's assertion that he is eligible for the ETC B. Must exercise due diligence only as to Taxpayer X's EITC eligibility O C.Must exercise due diligence only as to the amount of Taxpayer X's EITC D. Must exercise due diligence both as to Taxpayer X's EITC eligibility and the amount of the EITC