$1.$ Which of the following events that occurred after a client$$s calendar$-$year end, but before the audit report date, would require disclosure in the notes to financial statements, but no adjustment in the financial statements?

a$.$ New convertible bonds are issued to expand the company$$s product line

b$.$ A loss is reported on uncollectible accounts of an acknowledged distressed customer.

c$.$ A fixed asset used in operations is sold at a substantial profit.

d$.$ Negotiations have resulted in compensation adjustments for union employees retroactive to the fourth quarter.