Copy&Paste variable range based on cell value

Hi community,

Worksheet 'Dump' contains data in column A:G, variable number of rows. The
data is sorted by column D descending (values being "c", "b", "a").
I want to copy & paste only the rows with "c"'s and "b"'s
So, I need a macro that
- finds the last row of my needed range (as soon the macro finds an "a" in
cell Dx)
- selects the range (column A,B, row 1 to last needed row) and copies it
to a worksheet "Comments" to cell A1

Thanks a bunch in advance for your help
Thomas