(N/A) After proposing the double helical structure of $DNA$, Watson and Crick immediately proposed a scheme for $DNA$ replication.
The essence of their original statement is as follows: "It has not escaped our notice that the specific pairing we have postulated immediately suggests a possible copying mechanism for the genetic material."
According to this scheme, the two strands of $DNA$ separate and each strand acts as a template for the synthesis of a new complementary strand.
After replication, each $DNA$ molecule consists of one parental strand and one newly synthesized strand.
This scheme is known as the semi-conservative replication of $DNA$.