Claude Friese-Greene colour - a 2-color process, in this case, being yellow & orange. The yellow dresses definitely give a sense of happiness and spring daffodils, so this clip came to mind. Do we know what color dresses they were REALLY wearing? No, and unfortunately, we probably never will.
The film is essentially a giant vaudeville show, with 2 numbers performed by The Charlot Girls, who (apparently) got their name from one of the directors of the film, Andre Charlot.
Charlot was born in Paris, and eventually became an assistant manager of multiple big-name theaters, including the Folies Bergère and the Théâtre du Palais-Royal, before relocating to London in 1912.
Not much is known of The Charlot Girls. On this YouTube clip, one viewer made a comment below: "Love This! My grandmother, Marie Link, was a Charlot Girl (and before that with the Mistanguett and Maurice Chevalier in the Folies Bergeres in Paris)."
According to IMDB, they are credited with performing in 3 films, all produced in 1930. Here, they dance dressed as "ladies maids", with yellow dresses, aprons, and pink-ish bonnets. The routine consists mostly of clean formation changes and solid kick-lines, making it easy to see a comparison to the Charlot Girls and the popular American dance troupe of the time, the Missouri Rockets (later to become The Rockettes).
One of the most charming part of this clip is around 1 minute in, when the twelve gals grab the tips of their bright and flowing skirts and kick along as they skip through formation changes, revealing cute little frilly tap shorts under their skirts. SO DARLING! Another wonderful moment occurs around 1:40, when the girls jump into a circle formation, linking arms behind one another, and kicking in a circular motion, reminiscent of a daffodil opening. The kick-line exit off stage is flawless, with the dancers performing a little tap-cross-step in conjunction with the movement, giving a ballet feeling to the flow.
Overall, this is a delightful little clip, so now I present, for your enjoyment, The Charlot Girls, in Elstree Calling (1930):