Mark Dies on March 6

Mark dies on March 6. Which, if any, of the following items is not included in his gross estate?

A) Interest earned (before death) on City of Cleveland bonds.
B) Cash dividend on stock owned by Mark-declaration date was February 4, and record date was March 4.
C) Federal income tax refund for a prior tax year-received on March 5.
D) Insurance recovery on auto accident that occurred on February 25.
E) Insurance recovery from theft of sailboat on March 7.