CREATE TABLE protein (common_name TEXT, protein_name TEXT, divergence_from_human_lineage DECIMAL, accession_number TEXT, sequence_length DECIMAL, sequence_identity_to_human_protein TEXT, institution_id TEXT)
CREATE TABLE institution (institution_id TEXT, institution TEXT, location TEXT, founded DECIMAL, type TEXT, enrollment DECIMAL, team TEXT, primary_conference TEXT, building_id TEXT)
CREATE TABLE building (building_id TEXT, name TEXT, street_address TEXT, years_as_tallest TEXT, height_feet DECIMAL, floors DECIMAL)

Show the institution type with the largest number of institutions.
SELECT type FROM institution GROUP BY type ORDER BY COUNT(*) DESC LIMIT 1
SELECT "type" FROM "institution" GROUP BY "type" ORDER BY COUNT(*) DESC NULLS LAST LIMIT 1