CREATE TABLE table_77931 ("String" TEXT, "Scientific pitch" TEXT, "Helmholtz pitch" TEXT, "Interval from middle C" TEXT, "Frequency  (  Hz  ) " FLOAT)

What is the scientific pitch when the Helmholtz pitch is D?
SELECT "Scientific pitch" FROM table_77931 WHERE "Helmholtz pitch" = 'd'
SELECT "Scientific pitch" FROM "table_77931" WHERE "Helmholtz pitch" = 'd'