what happens if session timeout is set to -1 in the web.xml file ?

By: premje*** On: Sat Jun 17 11:06:03 IST 2017     0 0 0	0
<session-config><session-timeout>-1</session-config></session-timeout> a. session will never expire b. session will expire after 15 min. c. session will expire after 60 min. d. session will not start	0