Question:
Which employer did Frank Pick work for in Mar, 1939?

Context:
 Frank Pick works for London Passenger Transport Board from Jul, 1933 to May, 1940. 
 Frank Pick works for Department for Transport from Jan, 1941 to Nov, 1941. 
 Frank Pick works for Underground Electric Railways Company of London from Jan, 1906 to Jul, 1933.

Answer:
Question:
Which employer did Frank Pick work for in Mar, 1939?

Context:
 Frank Pick works for London Passenger Transport Board from Jul, 1933 to May, 1940. 
 Frank Pick works for Department for Transport from Jan, 1941 to Nov, 1941. 
 Frank Pick works for Underground Electric Railways Company of London from Jan, 1906 to Jul, 1933.

Answer:
user
London Passenger Transport Board
assistant
Question:
Which employer did Frank Pick work for in Mar, 1939?

Context:
 Frank Pick works for London Passenger Transport Board from Jul, 1933 to May, 1940. 
 Frank Pick works for Department for Transport from Jan, 1941 to Nov, 1941. 
 Frank Pick works for Underground Electric Railways Company of London from Jan, 1906 to Jul, 1933.

Answer:
user
Department for Transport
Underground Electric Railways Company of London
assistant
Question:
Which employer did Frank Pick work for in Mar, 1939?

Context:
 Frank Pick works for London Passenger Transport Board from Jul, 1933 to May, 1940. 
 Frank Pick works for Department for Transport from Jan, 1941 to Nov, 1941. 
 Frank Pick works for Underground Electric Railways Company of London from Jan, 1906 to Jul, 1933.

Answer:
user
London Passenger Transport Board
assistant