Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE DEPARTMENT ( DNO VARCHAR, DName VARCHAR )
TABLE: CREATE TABLE MEMBER_OF ( DNO VARCHAR, FacID VARCHAR )
TABLE: CREATE TABLE FACULTY ( Lname VARCHAR, FacID VARCHAR )

### Question ###
Find the last names of faculties who are members of computer science department.

### Accurate SQL ###

SELECT T2.Lname FROM DEPARTMENT AS T1 JOIN FACULTY AS T2 ON T1.DNO = T3.DNO JOIN MEMBER_OF AS T3 ON T2.FacID = T3.FacID WHERE T1.DName = "Computer Science"