Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE table_name_99 (category VARCHAR, year VARCHAR, nominated_work VARCHAR)
### Question:
What categories had a Nominated work of yerma before 1992?
### Answer:
SELECT category FROM table_name_99 WHERE year < 1992 AND nominated_work = "yerma"