Which is the default isolation level in Oracle Database 12c?

Which is the default isolation level in Oracle Database 12c?

A.
serializable

B.
read-only

C.
read committed

D.
read uncommitted

Explanation:
http://docs.oracle.com/cd/B28359_01/server.111/b28318/consist.htm#CNCPT1312
(see the sentence that comes right after table 13-1)