What is the function of a crypto map on a PIX Firewall?

A.
To configure a pre-shared authentication key and associate the key with an IKE peer address or host name.

B.
To configure a pre-shared authentication key and associate the key with an IPSec peer address or host name.

C.
To specify which algorithms to use with the selected security protocol.

D.
To filter and classify the traffic to be protected.

Explanation:
Crypto map entries for IPSec set up security association parameters, tying toghter the various parts configured for IPSec,including the following;
* Which traffic should be protected by IPSec
Ref: Cisco Secure PIX Firewalls (Ciscopress) Page 215