CREATE TABLE table_66287 ("Proto-Germanic" CLOB, "West Germanic" CLOB, "Old English" CLOB, "German" CLOB, "Dutch" CLOB)

What's the Proto-Germanic when the Old English is /d/?
SELECT "Proto-Germanic" FROM table_66287 WHERE "Old English" = '/d/'
SELECT "Proto-Germanic" FROM "table_66287" WHERE "Old English" = '/d/'