What step is required by a taxpayer to make or revoke a Section 179 election?

a)  A taxpayer must file an amended return within the legal time limits for the tax year to which the election applies.

b)  A taxpayer may not make or revoke a Section 179 election once the tax return for the tax year for which the election applies has been filed.

c)  A Section 179 election may not be revoked.

d)  A taxpayer must send a written request to the IRS to adjust the original return.