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_53 (school VARCHAR, previous_conference VARCHAR, enrollment VARCHAR)
### Question:
Which school has an enrollment of A and had lost river as their previous conference?
### Answer:
SELECT school FROM table_name_53 WHERE previous_conference = "lost river" AND enrollment = "a"