Given a short query with keyphrases about a research idea in 2011 in the domain of artificial intelligence, recommend the relevant datasets to validate the research idea from options provided. A short description of the datasets is also provided to help you.

Query: I want to formulate the direct discriminant analysis in a kernel feature space.

Keyphrases: direct discriminant analysis

Dataset description:
USPS: USPS is a digit dataset automatically scanned from envelopes by the U.S. Postal Service containing a total of 9,298 16×16 pixel grayscale samples; the images are centered, normalized and show a broad range of font styles.
CCMixter: CCMixter is a singing voice separation dataset consisting of 50 full-length stereo tracks from ccMixter featuring many different musical genres. For each song there are three WAV files available: the background music, the voice signal, and their sum.
SNIPS: The SNIPS Natural Language Understanding benchmark is a dataset of over 16,000 crowdsourced queries distributed among 7 user intents of various complexity:   SearchCreativeWork (e.g. Find me the I, Robot television show), GetWeather (e.g.
HIGGS Data Set: The data has been produced using Monte Carlo simulations. The first 21 features (columns 2-22) are kinematic properties measured by the particle detectors in the accelerator.

Options:- A: USPS  B: CCMixter  C: SNIPS  D: HIGGS Data Set
USPS