CREATE TABLE table_19930 ("Series Ep." TEXT, "Episode" FLOAT, "Segment A" TEXT, "Segment B" TEXT, "Segment C" TEXT, "Segment D" TEXT)

What are the titles of segment c when segment d is motorcycle brake locks?
SELECT "Segment C" FROM table_19930 WHERE "Segment D" = 'Motorcycle Brake Locks'
SELECT "Segment C" FROM "table_19930" WHERE "Segment D" = 'Motorcycle Brake Locks'